/*
* Copyright (c) 2021, Jesse Buhagiar <jooster669@gmail.com>
* Copyright (c) 2021, Stephan Unverwerth <s.unverwerth@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include "SoftwareGLContext.h"
#include "GLStruct.h"
#include "SoftwareRasterizer.h"
#include <AK/Assertions.h>
#include <AK/Debug.h>
#include <AK/Format.h>
#include <AK/QuickSort.h>
#include <AK/TemporaryChange.h>
#include <AK/Variant.h>
#include <AK/Vector.h>
#include <LibGfx/Bitmap.h>
#include <LibGfx/Painter.h>
#include <LibGfx/Vector4.h>
using AK::dbgln;
namespace GL {
// FIXME: We should set this up when we create the context!
static constexpr size_t MATRIX_STACK_LIMIT = 1024;
#define APPEND_TO_CALL_LIST_AND_RETURN_IF_NEEDED(name, ...) \
if (should_append_to_listing()) { \
append_to_listing<&SoftwareGLContext::name>(__VA_ARGS__); \
if (!should_execute_after_appending_to_listing()) \
return; \
}
#define RETURN_WITH_ERROR_IF(condition, error) \
if (condition) { \
if (m_error == GL_NO_ERROR) \
m_error = error; \
return; \
}
#define RETURN_VALUE_WITH_ERROR_IF(condition, error, return_value) \
if (condition) { \
if (m_error == GL_NO_ERROR) \
m_error = error; \
return return_value; \
}
SoftwareGLContext::SoftwareGLContext(Gfx::Bitmap& frontbuffer)
: m_frontbuffer(frontbuffer)
, m_rasterizer(frontbuffer.size())
{
}
void SoftwareGLContext::gl_begin(GLenum mode)
{
APPEND_TO_CALL_LIST_AND_RETURN_IF_NEEDED(gl_begin, mode);
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
RETURN_WITH_ERROR_IF(mode < GL_TRIANGLES || mode > GL_POLYGON, GL_INVALID_ENUM);
m_current_draw_mode = mode;
m_in_draw_state = true; // Certain commands will now generate an error
}
void SoftwareGLContext::gl_clear(GLbitfield mask)
{
APPEND_TO_CALL_LIST_AND_RETURN_IF_NEEDED(gl_clear, mask);
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
RETURN_WITH_ERROR_IF(mask & ~(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT), GL_INVALID_ENUM);
if (mask & GL_COLOR_BUFFER_BIT)
m_rasterizer.clear_color(m_clear_color);
if (mask & GL_DEPTH_BUFFER_BIT)
m_rasterizer.clear_depth(static_cast<float>(m_clear_depth));
}
void SoftwareGLContext::gl_clear_color(GLclampf red, GLclampf green, GLclampf blue, GLclampf alpha)
{
APPEND_TO_CALL_LIST_AND_RETURN_IF_NEEDED(gl_clear_color, red, green, blue, alpha);
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
m_clear_color = { red, green, blue, alpha };
}
void SoftwareGLContext::gl_clear_depth(GLdouble depth)
{
APPEND_TO_CALL_LIST_AND_RETURN_IF_NEEDED(gl_clear_depth, depth);
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
m_clear_depth = depth;
}
void SoftwareGLContext::gl_color(GLdouble r, GLdouble g, GLdouble b, GLdouble a)
{
APPEND_TO_CALL_LIST_AND_RETURN_IF_NEEDED(gl_color, r, g, b, a);
m_current_vertex_color = { (float)r, (float)g, (float)b, (float)a };
}
void SoftwareGLContext::gl_end()
{
APPEND_TO_CALL_LIST_AND_RETURN_IF_NEEDED(gl_end);
// At this point, the user has effectively specified that they are done with defining the geometry
// of what they want to draw. We now need to do a few things (https://www.khronos.org/opengl/wiki/Rendering_Pipeline_Overview):
//
// 1. Transform all of the vertices in the current vertex list into eye space by mulitplying the model-view matrix
// 2. Transform all of the vertices from eye space into clip space by multiplying by the projection matrix
// 3. If culling is enabled, we cull the desired faces (https://learnopengl.com/Advanced-OpenGL/Face-culling)
// 4. Each element of the vertex is then divided by w to bring the positions into NDC (Normalized Device Coordinates)
// 5. The vertices are sorted (for the rasteriser, how are we doing this? 3Dfx did this top to bottom in terms of vertex y coordinates)
// 6. The vertices are then sent off to the rasteriser and drawn to the screen
float scr_width = m_frontbuffer->width();
float scr_height = m_frontbuffer->height();
// Make sure we had a `glBegin` before this call...
RETURN_WITH_ERROR_IF(!m_in_draw_state, GL_INVALID_OPERATION);
triangle_list.clear_with_capacity();
processed_triangles.clear_with_capacity();
// Let's construct some triangles
if (m_current_draw_mode == GL_TRIANGLES) {
GLTriangle triangle;
for (size_t i = 0; i < vertex_list.size(); i += 3) {
triangle.vertices[0] = vertex_list.at(i);
triangle.vertices[1] = vertex_list.at(i + 1);
triangle.vertices[2] = vertex_list.at(i + 2);
triangle_list.append(triangle);
}
} else if (m_current_draw_mode == GL_QUADS) {
// We need to construct two triangles to form the quad
GLTriangle triangle;
VERIFY(vertex_list.size() % 4 == 0);
for (size_t i = 0; i < vertex_list.size(); i += 4) {
// Triangle 1
triangle.vertices[0] = vertex_list.at(i);
triangle.vertices[1] = vertex_list.at(i + 1);
triangle.vertices[2] = vertex_list.at(i + 2);
triangle_list.append(triangle);
// Triangle 2
triangle.vertices[0] = vertex_list.at(i + 2);
triangle.vertices[1] = vertex_list.at(i + 3);
triangle.vertices[2] = vertex_list.at(i);
triangle_list.append(triangle);
}
} else if (m_current_draw_mode == GL_TRIANGLE_FAN) {
GLTriangle triangle;
triangle.vertices[0] = vertex_list.at(0); // Root vertex is always the vertex defined first
for (size_t i = 1; i < vertex_list.size() - 1; i++) // This is technically `n-2` triangles. We start at index 1
{
triangle.vertices[1] = vertex_list.at(i);
triangle.vertices[2] = vertex_list.at(i + 1);
triangle_list.append(triangle);
}
} else if (m_current_draw_mode == GL_TRIANGLE_STRIP) {
GLTriangle triangle;
for (size_t i = 0; i < vertex_list.size() - 2; i++) {
triangle.vertices[0] = vertex_list.at(i);
triangle.vertices[1] = vertex_list.at(i + 1);
triangle.vertices[2] = vertex_list.at(i + 2);
triangle_list.append(triangle);
}
} else {
vertex_list.clear_with_capacity();
RETURN_WITH_ERROR_IF(true, GL_INVALID_ENUM);
}
vertex_list.clear_with_capacity();
auto mvp = m_projection_matrix * m_model_view_matrix;
// Now let's transform each triangle and send that to the GPU
for (size_t i = 0; i < triangle_list.size(); i++) {
GLTriangle& triangle = triangle_list.at(i);
// First multiply the vertex by the MODELVIEW matrix and then the PROJECTION matrix
triangle.vertices[0].position = mvp * triangle.vertices[0].position;
triangle.vertices[1].position = mvp * triangle.vertices[1].position;
triangle.vertices[2].position = mvp * triangle.vertices[2].position;
// At this point, we're in clip space
// Here's where we do the clipping. This is a really crude implementation of the
// https://learnopengl.com/Getting-started/Coordinate-Systems
// "Note that if only a part of a primitive e.g. a triangle is outside the clipping volume OpenGL
// will reconstruct the triangle as one or more triangles to fit inside the clipping range. "
//
// ALL VERTICES ARE DEFINED IN A CLOCKWISE ORDER
// Okay, let's do some face culling first
m_clipped_vertices.clear_with_capacity();
m_clipped_vertices.append(triangle.vertices[0]);
m_clipped_vertices.append(triangle.vertices[1]);
m_clipped_vertices.append(triangle.vertices[2]);
m_clipper.clip_triangle_against_frustum(m_clipped_vertices);
if (m_clipped_vertices.size() < 3)
continue;
for (auto& vec : m_clipped_vertices) {
// perspective divide
float w = vec.position.w();
vec.position.set_x(vec.position.x() / w);
vec.position.set_y(vec.position.y() / w);
vec.position.set_z(vec.position.z() / w);
vec.position.set_w(1 / w);
// to screen space
vec.position.set_x(scr_width / 2 + vec.position.x() * scr_width / 2);
vec.position.set_y(scr_height / 2 - vec.position.y() * scr_height / 2);
}
GLTriangle tri;
tri.vertices[0] = m_clipped_vertices[0];
for (size_t i = 1; i < m_clipped_vertices.size() - 1; i++) {
tri.vertices[1] = m_clipped_vertices[i];
tri.vertices[2] = m_clipped_vertices[i + 1];
processed_triangles.append(tri);
}
}
for (size_t i = 0; i < processed_triangles.size(); i++) {
GLTriangle& triangle = processed_triangles.at(i);
// Let's calculate the (signed) area of the triangle
// https://cp-algorithms.com/geometry/oriented-triangle-area.html
float dxAB = triangle.vertices[0].position.x() - triangle.vertices[1].position.x(); // A.x - B.x
float dxBC = triangle.vertices[1].position.x() - triangle.vertices[2].position.x(); // B.X - C.x
float dyAB = triangle.vertices[0].position.y() - triangle.vertices[1].position.y();
float dyBC = triangle.vertices[1].position.y() - triangle.vertices[2].position.y();
float area = (dxAB * dyBC) - (dxBC * dyAB);
if (area == 0.0f)
continue;
if (m_cull_faces) {
bool is_front = (m_front_face == GL_CCW ? area < 0 : area > 0);
if (is_front && (m_culled_sides == GL_FRONT || m_culled_sides == GL_FRONT_AND_BACK))
continue;
if (!is_front && (m_culled_sides == GL_BACK || m_culled_sides == GL_FRONT_AND_BACK))
continue;
}
if (area > 0) {
swap(triangle.vertices[0], triangle.vertices[1]);
}
m_rasterizer.submit_triangle(triangle, m_texture_units);
}
m_in_draw_state = false;
}
void SoftwareGLContext::gl_frustum(GLdouble left, GLdouble right, GLdouble bottom, GLdouble top, GLdouble near_val, GLdouble far_val)
{
APPEND_TO_CALL_LIST_AND_RETURN_IF_NEEDED(gl_frustum, left, right, bottom, top, near_val, far_val);
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
// Let's do some math!
// FIXME: Are we losing too much precision by doing this?
float a = static_cast<float>((right + left) / (right - left));
float b = static_cast<float>((top + bottom) / (top - bottom));
float c = static_cast<float>(-((far_val + near_val) / (far_val - near_val)));
float d = static_cast<float>(-((2 * (far_val * near_val)) / (far_val - near_val)));
FloatMatrix4x4 frustum {
((2 * (float)near_val) / ((float)right - (float)left)), 0, a, 0,
0, ((2 * (float)near_val) / ((float)top - (float)bottom)), b, 0,
0, 0, c, d,
0, 0, -1, 0
};
if (m_current_matrix_mode == GL_PROJECTION) {
m_projection_matrix = m_projection_matrix * frustum;
} else if (m_current_matrix_mode == GL_MODELVIEW) {
dbgln_if(GL_DEBUG, "glFrustum(): frustum created with curr_matrix_mode == GL_MODELVIEW!!!");
m_projection_matrix = m_model_view_matrix * frustum;
}
}
void SoftwareGLContext::gl_ortho(GLdouble left, GLdouble right, GLdouble bottom, GLdouble top, GLdouble near_val, GLdouble far_val)
{
APPEND_TO_CALL_LIST_AND_RETURN_IF_NEEDED(gl_ortho, left, right, bottom, top, near_val, far_val);
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
RETURN_WITH_ERROR_IF(left == right || bottom == top || near_val == far_val, GL_INVALID_VALUE);
auto rl = right - left;
auto tb = top - bottom;
auto fn = far_val - near_val;
auto tx = -(right + left) / rl;
auto ty = -(top + bottom) / tb;
auto tz = -(far_val + near_val) / fn;
FloatMatrix4x4 projection {
static_cast<float>(2 / rl), 0, 0, static_cast<float>(tx),
0, static_cast<float>(2 / tb), 0, static_cast<float>(ty),
0, 0, static_cast<float>(-2 / fn), static_cast<float>(tz),
0, 0, 0, 1
};
if (m_current_matrix_mode == GL_PROJECTION) {
m_projection_matrix = m_projection_matrix * projection;
} else if (m_current_matrix_mode == GL_MODELVIEW) {
m_projection_matrix = m_model_view_matrix * projection;
}
}
GLenum SoftwareGLContext::gl_get_error()
{
if (m_in_draw_state)
return GL_INVALID_OPERATION;
auto last_error = m_error;
m_error = GL_NO_ERROR;
return last_error;
}
GLubyte* SoftwareGLContext::gl_get_string(GLenum name)
{
RETURN_VALUE_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION, nullptr);
switch (name) {
case GL_VENDOR:
return reinterpret_cast<GLubyte*>(const_cast<char*>("The SerenityOS Developers"));
case GL_RENDERER:
return reinterpret_cast<GLubyte*>(const_cast<char*>("SerenityOS OpenGL"));
case GL_VERSION:
return reinterpret_cast<GLubyte*>(const_cast<char*>("1.5"));
case GL_EXTENSIONS:
return reinterpret_cast<GLubyte*>(const_cast<char*>(""));
default:
dbgln_if(GL_DEBUG, "glGetString(): Unknown enum name!");
break;
}
RETURN_VALUE_WITH_ERROR_IF(true, GL_INVALID_ENUM, nullptr);
}
void SoftwareGLContext::gl_load_identity()
{
APPEND_TO_CALL_LIST_AND_RETURN_IF_NEEDED(gl_load_identity);
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
if (m_current_matrix_mode == GL_PROJECTION)
m_projection_matrix = FloatMatrix4x4::identity();
else if (m_current_matrix_mode == GL_MODELVIEW)
m_model_view_matrix = FloatMatrix4x4::identity();
else
VERIFY_NOT_REACHED();
}
void SoftwareGLContext::gl_load_matrix(const FloatMatrix4x4& matrix)
{
if (should_append_to_listing()) {
auto ptr = store_in_listing(matrix);
append_to_listing<&SoftwareGLContext::gl_load_matrix>(*ptr);
if (!should_execute_after_appending_to_listing())
return;
}
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
if (m_current_matrix_mode == GL_PROJECTION)
m_projection_matrix = matrix;
else if (m_current_matrix_mode == GL_MODELVIEW)
m_model_view_matrix = matrix;
else
VERIFY_NOT_REACHED();
}
void SoftwareGLContext::gl_matrix_mode(GLenum mode)
{
APPEND_TO_CALL_LIST_AND_RETURN_IF_NEEDED(gl_matrix_mode, mode);
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
RETURN_WITH_ERROR_IF(mode < GL_MODELVIEW || mode > GL_PROJECTION, GL_INVALID_ENUM);
m_current_matrix_mode = mode;
}
void SoftwareGLContext::gl_push_matrix()
{
APPEND_TO_CALL_LIST_AND_RETURN_IF_NEEDED(gl_push_matrix);
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
dbgln_if(GL_DEBUG, "glPushMatrix(): Pushing matrix to the matrix stack (matrix_mode {})", m_current_matrix_mode);
switch (m_current_matrix_mode) {
case GL_PROJECTION:
RETURN_WITH_ERROR_IF(m_projection_matrix_stack.size() >= MATRIX_STACK_LIMIT, GL_STACK_OVERFLOW);
m_projection_matrix_stack.append(m_projection_matrix);
break;
case GL_MODELVIEW:
RETURN_WITH_ERROR_IF(m_model_view_matrix_stack.size() >= MATRIX_STACK_LIMIT, GL_STACK_OVERFLOW);
m_model_view_matrix_stack.append(m_model_view_matrix);
break;
default:
dbgln_if(GL_DEBUG, "glPushMatrix(): Attempt to push matrix with invalid matrix mode {})", m_current_matrix_mode);
return;
}
}
void SoftwareGLContext::gl_pop_matrix()
{
APPEND_TO_CALL_LIST_AND_RETURN_IF_NEEDED(gl_pop_matrix);
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
dbgln_if(GL_DEBUG, "glPopMatrix(): Popping matrix from matrix stack (matrix_mode = {})", m_current_matrix_mode);
// FIXME: Make sure stack::top() doesn't cause any nasty issues if it's empty (that could result in a lockup/hang)
switch (m_current_matrix_mode) {
case GL_PROJECTION:
RETURN_WITH_ERROR_IF(m_projection_matrix_stack.size() == 0, GL_STACK_UNDERFLOW);
m_projection_matrix = m_projection_matrix_stack.take_last();
break;
case GL_MODELVIEW:
RETURN_WITH_ERROR_IF(m_model_view_matrix_stack.size() == 0, GL_STACK_UNDERFLOW);
m_model_view_matrix = m_model_view_matrix_stack.take_last();
break;
default:
dbgln_if(GL_DEBUG, "glPopMatrix(): Attempt to pop matrix with invalid matrix mode, {}", m_current_matrix_mode);
return;
}
}
void SoftwareGLContext::gl_rotate(GLdouble angle, GLdouble x, GLdouble y, GLdouble z)
{
APPEND_TO_CALL_LIST_AND_RETURN_IF_NEEDED(gl_rotate, angle, x, y, z);
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
FloatVector3 axis = { (float)x, (float)y, (float)z };
axis.normalize();
auto rotation_mat = Gfx::rotation_matrix(axis, static_cast<float>(angle * M_PI * 2 / 360));
if (m_current_matrix_mode == GL_MODELVIEW)
m_model_view_matrix = m_model_view_matrix * rotation_mat;
else if (m_current_matrix_mode == GL_PROJECTION)
m_projection_matrix = m_projection_matrix * rotation_mat;
}
void SoftwareGLContext::gl_scale(GLdouble x, GLdouble y, GLdouble z)
{
APPEND_TO_CALL_LIST_AND_RETURN_IF_NEEDED(gl_scale, x, y, z);
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
if (m_current_matrix_mode == GL_MODELVIEW) {
m_model_view_matrix = m_model_view_matrix * Gfx::scale_matrix(FloatVector3 { static_cast<float>(x), static_cast<float>(y), static_cast<float>(z) });
} else if (m_current_matrix_mode == GL_PROJECTION) {
m_projection_matrix = m_projection_matrix * Gfx::scale_matrix(FloatVector3 { static_cast<float>(x), static_cast<float>(y), static_cast<float>(z) });
}
}
void SoftwareGLContext::gl_translate(GLdouble x, GLdouble y, GLdouble z)
{
APPEND_TO_CALL_LIST_AND_RETURN_IF_NEEDED(gl_translate, x, y, z);
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
if (m_current_matrix_mode == GL_MODELVIEW) {
m_model_view_matrix = m_model_view_matrix * Gfx::translation_matrix(FloatVector3 { (float)x, (float)y, (float)z });
} else if (m_current_matrix_mode == GL_PROJECTION) {
m_projection_matrix = m_projection_matrix * Gfx::translation_matrix(FloatVector3 { (float)x, (float)y, (float)z });
}
}
void SoftwareGLContext::gl_vertex(GLdouble x, GLdouble y, GLdouble z, GLdouble w)
{
APPEND_TO_CALL_LIST_AND_RETURN_IF_NEEDED(gl_vertex, x, y, z, w);
GLVertex vertex;
vertex.position = { static_cast<float>(x), static_cast<float>(y), static_cast<float>(z), static_cast<float>(w) };
vertex.color = m_current_vertex_color;
vertex.tex_coord = { m_current_vertex_tex_coord.x(), m_current_vertex_tex_coord.y() };
vertex_list.append(vertex);
}
// FIXME: We need to add `r` and `q` to our GLVertex?!
void SoftwareGLContext::gl_tex_coord(GLfloat s, GLfloat t, GLfloat r, GLfloat q)
{
APPEND_TO_CALL_LIST_AND_RETURN_IF_NEEDED(gl_tex_coord, s, t, r, q);
m_current_vertex_tex_coord = { s, t, r, q };
}
void SoftwareGLContext::gl_viewport(GLint x, GLint y, GLsizei width, GLsizei height)
{
APPEND_TO_CALL_LIST_AND_RETURN_IF_NEEDED(gl_viewport, x, y, width, height);
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
(void)(x);
(void)(y);
(void)(width);
(void)(height);
}
void SoftwareGLContext::gl_enable(GLenum capability)
{
APPEND_TO_CALL_LIST_AND_RETURN_IF_NEEDED(gl_enable, capability);
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
auto rasterizer_options = m_rasterizer.options();
bool update_rasterizer_options = false;
switch (capability) {
case GL_CULL_FACE:
m_cull_faces = true;
break;
case GL_DEPTH_TEST:
m_depth_test_enabled = true;
rasterizer_options.enable_depth_test = true;
update_rasterizer_options = true;
break;
case GL_BLEND:
m_blend_enabled = true;
rasterizer_options.enable_blending = true;
update_rasterizer_options = true;
break;
case GL_ALPHA_TEST:
m_alpha_test_enabled = true;
rasterizer_options.enable_alpha_test = true;
update_rasterizer_options = true;
break;
case GL_FOG:
rasterizer_options.fog_enabled = true;
update_rasterizer_options = true;
break;
default:
RETURN_WITH_ERROR_IF(true, GL_INVALID_ENUM);
}
if (update_rasterizer_options)
m_rasterizer.set_options(rasterizer_options);
}
void SoftwareGLContext::gl_disable(GLenum capability)
{
APPEND_TO_CALL_LIST_AND_RETURN_IF_NEEDED(gl_disable, capability);
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
auto rasterizer_options = m_rasterizer.options();
bool update_rasterizer_options = false;
switch (capability) {
case GL_CULL_FACE:
m_cull_faces = false;
break;
case GL_DEPTH_TEST:
m_depth_test_enabled = false;
rasterizer_options.enable_depth_test = false;
update_rasterizer_options = true;
break;
case GL_BLEND:
m_blend_enabled = false;
rasterizer_options.enable_blending = false;
update_rasterizer_options = true;
break;
case GL_ALPHA_TEST:
m_alpha_test_enabled = false;
rasterizer_options.enable_alpha_test = false;
update_rasterizer_options = true;
break;
default:
RETURN_WITH_ERROR_IF(true, GL_INVALID_ENUM);
}
if (update_rasterizer_options)
m_rasterizer.set_options(rasterizer_options);
}
void SoftwareGLContext::gl_gen_textures(GLsizei n, GLuint* textures)
{
RETURN_WITH_ERROR_IF(n < 0, GL_INVALID_VALUE);
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
m_name_allocator.allocate(n, textures);
// Initialize all texture names with a nullptr
for (auto i = 0; i < n; i++) {
GLuint name = textures[i];
m_allocated_textures.set(name, nullptr);
}
}
void SoftwareGLContext::gl_delete_textures(GLsizei n, const GLuint* textures)
{
RETURN_WITH_ERROR_IF(n < 0, GL_INVALID_VALUE);
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
m_name_allocator.free(n, textures);
for (auto i = 0; i < n; i++) {
GLuint name = textures[i];
auto texture_object = m_allocated_textures.find(name);
if (texture_object == m_allocated_textures.end() || texture_object->value.is_null())
continue;
// Check all texture units
for (auto& texture_unit : m_texture_units) {
if (texture_object->value == texture_unit.bound_texture())
texture_unit.unbind_texture(GL_TEXTURE_2D);
}
m_allocated_textures.remove(name);
}
}
void SoftwareGLContext::gl_tex_image_2d(GLenum target, GLint level, GLint internal_format, GLsizei width, GLsizei height, GLint border, GLenum format, GLenum type, const GLvoid* data)
{
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
// We only support GL_TEXTURE_2D for now
RETURN_WITH_ERROR_IF(target != GL_TEXTURE_2D, GL_INVALID_ENUM);
// Check if there is actually a texture bound
RETURN_WITH_ERROR_IF(target == GL_TEXTURE_2D && m_active_texture_unit->currently_bound_target() != GL_TEXTURE_2D, GL_INVALID_OPERATION);
// We only support symbolic constants for now
RETURN_WITH_ERROR_IF(!(internal_format == GL_RGB || internal_format == GL_RGBA), GL_INVALID_ENUM);
RETURN_WITH_ERROR_IF(type != GL_UNSIGNED_BYTE, GL_INVALID_VALUE);
RETURN_WITH_ERROR_IF(level < 0 || level > Texture2D::LOG2_MAX_TEXTURE_SIZE, GL_INVALID_VALUE);
RETURN_WITH_ERROR_IF(width < 0 || height < 0 || width > (2 + Texture2D::MAX_TEXTURE_SIZE) || height > (2 + Texture2D::MAX_TEXTURE_SIZE), GL_INVALID_VALUE);
RETURN_WITH_ERROR_IF((width & 2) != 0 || (height & 2) != 0, GL_INVALID_VALUE);
RETURN_WITH_ERROR_IF(border < 0 || border > 1, GL_INVALID_VALUE);
m_active_texture_unit->bound_texture_2d()->upload_texture_data(target, level, internal_format, width, height, border, format, type, data, m_unpack_row_length);
}
void SoftwareGLContext::gl_tex_parameter(GLenum target, GLenum pname, GLfloat param)
{
APPEND_TO_CALL_LIST_AND_RETURN_IF_NEEDED(gl_tex_parameter, target, pname, param);
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
// FIXME: We currently only support GL_TETXURE_2D targets. 1D, 3D and CUBE should also be supported (https://docs.gl/gl2/glTexParameter)
RETURN_WITH_ERROR_IF(target != GL_TEXTURE_2D, GL_INVALID_ENUM);
// FIXME: implement the remaining parameters. (https://docs.gl/gl2/glTexParameter)
RETURN_WITH_ERROR_IF(!(pname == GL_TEXTURE_MIN_FILTER
|| pname == GL_TEXTURE_MAG_FILTER
|| pname == GL_TEXTURE_WRAP_S
|| pname == GL_TEXTURE_WRAP_T),
GL_INVALID_ENUM);
if (target == GL_TEXTURE_2D) {
auto texture2d = m_active_texture_unit->bound_texture_2d();
if (texture2d.is_null())
return;
switch (pname) {
case GL_TEXTURE_MIN_FILTER:
RETURN_WITH_ERROR_IF(!(param == GL_NEAREST
|| param == GL_LINEAR
|| param == GL_NEAREST_MIPMAP_NEAREST
|| param == GL_LINEAR_MIPMAP_NEAREST
|| param == GL_NEAREST_MIPMAP_LINEAR
|| param == GL_LINEAR_MIPMAP_LINEAR),
GL_INVALID_ENUM);
texture2d->sampler().set_min_filter(param);
break;
case GL_TEXTURE_MAG_FILTER:
RETURN_WITH_ERROR_IF(!(param == GL_NEAREST
|| param == GL_LINEAR),
GL_INVALID_ENUM);
texture2d->sampler().set_mag_filter(param);
break;
case GL_TEXTURE_WRAP_S:
RETURN_WITH_ERROR_IF(!(param == GL_CLAMP
|| param == GL_CLAMP_TO_BORDER
|| param == GL_CLAMP_TO_EDGE
|| param == GL_MIRRORED_REPEAT
|| param == GL_REPEAT),
GL_INVALID_ENUM);
texture2d->sampler().set_wrap_s_mode(param);
break;
case GL_TEXTURE_WRAP_T:
RETURN_WITH_ERROR_IF(!(param == GL_CLAMP
|| param == GL_CLAMP_TO_BORDER
|| param == GL_CLAMP_TO_EDGE
|| param == GL_MIRRORED_REPEAT
|| param == GL_REPEAT),
GL_INVALID_ENUM);
texture2d->sampler().set_wrap_t_mode(param);
break;
default:
VERIFY_NOT_REACHED();
}
}
}
void SoftwareGLContext::gl_front_face(GLenum face)
{
APPEND_TO_CALL_LIST_AND_RETURN_IF_NEEDED(gl_front_face, face);
RETURN_WITH_ERROR_IF(face < GL_CW || face > GL_CCW, GL_INVALID_ENUM);
m_front_face = face;
}
void SoftwareGLContext::gl_cull_face(GLenum cull_mode)
{
APPEND_TO_CALL_LIST_AND_RETURN_IF_NEEDED(gl_cull_face, cull_mode);
RETURN_WITH_ERROR_IF(cull_mode < GL_FRONT || cull_mode > GL_FRONT_AND_BACK, GL_INVALID_ENUM);
m_culled_sides = cull_mode;
}
GLuint SoftwareGLContext::gl_gen_lists(GLsizei range)
{
RETURN_VALUE_WITH_ERROR_IF(range <= 0, GL_INVALID_VALUE, 0);
RETURN_VALUE_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION, 0);
auto initial_entry = m_listings.size();
m_listings.resize(range + initial_entry);
return initial_entry + 1;
}
void SoftwareGLContext::gl_call_list(GLuint list)
{
if (m_gl_call_depth > max_allowed_gl_call_depth)
return;
APPEND_TO_CALL_LIST_AND_RETURN_IF_NEEDED(gl_call_list, list);
if (m_listings.size() < list)
return;
TemporaryChange change { m_gl_call_depth, m_gl_call_depth + 1 };
auto& listing = m_listings[list - 1];
for (auto& entry : listing.entries) {
entry.function.visit([&](auto& function) {
entry.arguments.visit([&](auto& arguments) {
auto apply = [&]<typename... Args>(Args && ... args)
{
if constexpr (requires { (this->*function)(forward<Args>(args)...); })
(this->*function)(forward<Args>(args)...);
};
arguments.apply_as_args(apply);
});
});
}
}
void SoftwareGLContext::gl_delete_lists(GLuint list, GLsizei range)
{
if (m_listings.size() < list || m_listings.size() <= list + range)
return;
for (auto& entry : m_listings.span().slice(list - 1, range))
entry.entries.clear_with_capacity();
}
void SoftwareGLContext::gl_end_list()
{
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
RETURN_WITH_ERROR_IF(!m_current_listing_index.has_value(), GL_INVALID_OPERATION);
m_listings[m_current_listing_index->index] = move(m_current_listing_index->listing);
m_current_listing_index.clear();
}
void SoftwareGLContext::gl_new_list(GLuint list, GLenum mode)
{
RETURN_WITH_ERROR_IF(list == 0, GL_INVALID_VALUE);
RETURN_WITH_ERROR_IF(mode != GL_COMPILE && mode != GL_COMPILE_AND_EXECUTE, GL_INVALID_ENUM);
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
RETURN_WITH_ERROR_IF(m_current_listing_index.has_value(), GL_INVALID_OPERATION);
if (m_listings.size() < list)
return;
m_current_listing_index = CurrentListing { {}, static_cast<size_t>(list - 1), mode };
}
void SoftwareGLContext::gl_flush()
{
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
// No-op since SoftwareGLContext is completely synchronous at the moment
}
void SoftwareGLContext::gl_finish()
{
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
// No-op since SoftwareGLContext is completely synchronous at the moment
}
void SoftwareGLContext::gl_blend_func(GLenum src_factor, GLenum dst_factor)
{
APPEND_TO_CALL_LIST_AND_RETURN_IF_NEEDED(gl_blend_func, src_factor, dst_factor);
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
// FIXME: The list of allowed enums differs between API versions
// This was taken from the 2.0 spec on https://docs.gl/gl2/glBlendFunc
RETURN_WITH_ERROR_IF(!(src_factor == GL_ZERO
|| src_factor == GL_ONE
|| src_factor == GL_SRC_COLOR
|| src_factor == GL_ONE_MINUS_SRC_COLOR
|| src_factor == GL_DST_COLOR
|| src_factor == GL_ONE_MINUS_DST_COLOR
|| src_factor == GL_SRC_ALPHA
|| src_factor == GL_ONE_MINUS_SRC_ALPHA
|| src_factor == GL_DST_ALPHA
|| src_factor == GL_ONE_MINUS_DST_ALPHA
|| src_factor == GL_CONSTANT_COLOR
|| src_factor == GL_ONE_MINUS_CONSTANT_COLOR
|| src_factor == GL_CONSTANT_ALPHA
|| src_factor == GL_ONE_MINUS_CONSTANT_ALPHA
|| src_factor == GL_SRC_ALPHA_SATURATE),
GL_INVALID_ENUM);
RETURN_WITH_ERROR_IF(!(dst_factor == GL_ZERO
|| dst_factor == GL_ONE
|| dst_factor == GL_SRC_COLOR
|| dst_factor == GL_ONE_MINUS_SRC_COLOR
|| dst_factor == GL_DST_COLOR
|| dst_factor == GL_ONE_MINUS_DST_COLOR
|| dst_factor == GL_SRC_ALPHA
|| dst_factor == GL_ONE_MINUS_SRC_ALPHA
|| dst_factor == GL_DST_ALPHA
|| dst_factor == GL_ONE_MINUS_DST_ALPHA
|| dst_factor == GL_CONSTANT_COLOR
|| dst_factor == GL_ONE_MINUS_CONSTANT_COLOR
|| dst_factor == GL_CONSTANT_ALPHA
|| dst_factor == GL_ONE_MINUS_CONSTANT_ALPHA),
GL_INVALID_ENUM);
m_blend_source_factor = src_factor;
m_blend_destination_factor = dst_factor;
auto options = m_rasterizer.options();
options.blend_source_factor = m_blend_source_factor;
options.blend_destination_factor = m_blend_destination_factor;
m_rasterizer.set_options(options);
}
void SoftwareGLContext::gl_shade_model(GLenum mode)
{
APPEND_TO_CALL_LIST_AND_RETURN_IF_NEEDED(gl_shade_model, mode);
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
RETURN_WITH_ERROR_IF(mode != GL_FLAT && mode != GL_SMOOTH, GL_INVALID_ENUM);
auto options = m_rasterizer.options();
options.shade_smooth = (mode == GL_SMOOTH);
m_rasterizer.set_options(options);
}
void SoftwareGLContext::gl_alpha_func(GLenum func, GLclampf ref)
{
APPEND_TO_CALL_LIST_AND_RETURN_IF_NEEDED(gl_alpha_func, func, ref);
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
RETURN_WITH_ERROR_IF(func < GL_NEVER || func > GL_ALWAYS, GL_INVALID_ENUM);
m_alpha_test_func = func;
m_alpha_test_ref_value = ref;
auto options = m_rasterizer.options();
options.alpha_test_func = m_alpha_test_func;
options.alpha_test_ref_value = m_alpha_test_ref_value;
m_rasterizer.set_options(options);
}
void SoftwareGLContext::gl_hint(GLenum target, GLenum mode)
{
APPEND_TO_CALL_LIST_AND_RETURN_IF_NEEDED(gl_hint, target, mode);
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
RETURN_WITH_ERROR_IF(target != GL_PERSPECTIVE_CORRECTION_HINT
&& target != GL_POINT_SMOOTH_HINT
&& target != GL_LINE_SMOOTH_HINT
&& target != GL_POLYGON_SMOOTH_HINT
&& target != GL_FOG_HINT
&& target != GL_GENERATE_MIPMAP_HINT
&& target != GL_TEXTURE_COMPRESSION_HINT,
GL_INVALID_ENUM);
RETURN_WITH_ERROR_IF(mode != GL_DONT_CARE
&& mode != GL_FASTEST
&& mode != GL_NICEST,
GL_INVALID_ENUM);
// According to the spec implementors are free to ignore glHint. So we do.
}
void SoftwareGLContext::gl_read_buffer(GLenum mode)
{
APPEND_TO_CALL_LIST_AND_RETURN_IF_NEEDED(gl_read_buffer, mode);
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
// FIXME: Also allow aux buffers GL_AUX0 through GL_AUX3 here
// plus any aux buffer between 0 and GL_AUX_BUFFERS
RETURN_WITH_ERROR_IF(mode != GL_FRONT_LEFT
&& mode != GL_FRONT_RIGHT
&& mode != GL_BACK_LEFT
&& mode != GL_BACK_RIGHT
&& mode != GL_FRONT
&& mode != GL_BACK
&& mode != GL_LEFT
&& mode != GL_RIGHT,
GL_INVALID_ENUM);
// FIXME: We do not currently have aux buffers, so make it an invalid
// operation to select anything but front or back buffers. Also we do
// not allow selecting the stereoscopic RIGHT buffers since we do not
// have them configured.
RETURN_WITH_ERROR_IF(mode != GL_FRONT_LEFT
&& mode != GL_FRONT
&& mode != GL_BACK_LEFT
&& mode != GL_BACK
&& mode != GL_FRONT
&& mode != GL_BACK
&& mode != GL_LEFT,
GL_INVALID_OPERATION);
m_current_read_buffer = mode;
}
void SoftwareGLContext::gl_read_pixels(GLint x, GLint y, GLsizei width, GLsizei height, GLenum format, GLenum type, GLvoid* pixels)
{
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
RETURN_WITH_ERROR_IF(width < 0 || height < 0, GL_INVALID_VALUE);
RETURN_WITH_ERROR_IF(format != GL_COLOR_INDEX
&& format != GL_STENCIL_INDEX
&& format != GL_DEPTH_COMPONENT
&& format != GL_RED
&& format != GL_GREEN
&& format != GL_BLUE
&& format != GL_ALPHA
&& format != GL_RGB
&& format != GL_RGBA
&& format != GL_LUMINANCE
&& format != GL_LUMINANCE_ALPHA,
GL_INVALID_ENUM);
RETURN_WITH_ERROR_IF(type != GL_UNSIGNED_BYTE
&& type != GL_BYTE
&& type != GL_BITMAP
&& type != GL_UNSIGNED_SHORT
&& type != GL_SHORT
&& type != GL_BLUE
&& type != GL_UNSIGNED_INT
&& type != GL_INT
&& type != GL_FLOAT,
GL_INVALID_ENUM);
// FIXME: We only support RGBA buffers for now.
// Once we add support for indexed color modes do the correct check here
RETURN_WITH_ERROR_IF(format == GL_COLOR_INDEX, GL_INVALID_OPERATION);
// FIXME: We do not have stencil buffers yet
// Once we add support for stencil buffers do the correct check here
RETURN_WITH_ERROR_IF(format == GL_STENCIL_INDEX, GL_INVALID_OPERATION);
if (format == GL_DEPTH_COMPONENT) {
// FIXME: This check needs to be a bit more sophisticated. Currently the buffers
// are hardcoded. Once we add proper structures for them we need to correct this check
// Error because only back buffer has a depth buffer
RETURN_WITH_ERROR_IF(m_current_read_buffer == GL_FRONT
|| m_current_read_buffer == GL_FRONT_LEFT
|| m_current_read_buffer == GL_FRONT_RIGHT,
GL_INVALID_OPERATION);
}
// Some helper functions for converting float values to integer types
auto float_to_i8 = [](float f) -> GLchar {
return static_cast<GLchar>((0x7f * min(max(f, 0.0f), 1.0f) - 1) / 2);
};
auto float_to_i16 = [](float f) -> GLshort {
return static_cast<GLshort>((0x7fff * min(max(f, 0.0f), 1.0f) - 1) / 2);
};
auto float_to_i32 = [](float f) -> GLint {
return static_cast<GLint>((0x7fffffff * min(max(f, 0.0f), 1.0f) - 1) / 2);
};
auto float_to_u8 = [](float f) -> GLubyte {
return static_cast<GLubyte>(0xff * min(max(f, 0.0f), 1.0f));
};
auto float_to_u16 = [](float f) -> GLushort {
return static_cast<GLushort>(0xffff * min(max(f, 0.0f), 1.0f));
};
auto float_to_u32 = [](float f) -> GLuint {
return static_cast<GLuint>(0xffffffff * min(max(f, 0.0f), 1.0f));
};
if (format == GL_DEPTH_COMPONENT) {
// Read from depth buffer
for (GLsizei i = 0; i < height; ++i) {
for (GLsizei j = 0; j < width; ++j) {
float depth = m_rasterizer.get_depthbuffer_value(x + j, y + i);
switch (type) {
case GL_BYTE:
reinterpret_cast<GLchar*>(pixels)[i * width + j] = float_to_i8(depth);
break;
case GL_SHORT:
reinterpret_cast<GLshort*>(pixels)[i * width + j] = float_to_i16(depth);
break;
case GL_INT:
reinterpret_cast<GLint*>(pixels)[i * width + j] = float_to_i32(depth);
break;
case GL_UNSIGNED_BYTE:
reinterpret_cast<GLubyte*>(pixels)[i * width + j] = float_to_u8(depth);
break;
case GL_UNSIGNED_SHORT:
reinterpret_cast<GLushort*>(pixels)[i * width + j] = float_to_u16(depth);
break;
case GL_UNSIGNED_INT:
reinterpret_cast<GLuint*>(pixels)[i * width + j] = float_to_u32(depth);
break;
case GL_FLOAT:
reinterpret_cast<GLfloat*>(pixels)[i * width + j] = min(max(depth, 0.0f), 1.0f);
break;
}
}
}
return;
}
bool write_red = false;
bool write_green = false;
bool write_blue = false;
bool write_alpha = false;
size_t component_count = 0;
size_t component_size = 0;
size_t red_offset = 0;
size_t green_offset = 0;
size_t blue_offset = 0;
size_t alpha_offset = 0;
char* red_ptr = nullptr;
char* green_ptr = nullptr;
char* blue_ptr = nullptr;
char* alpha_ptr = nullptr;
switch (format) {
case GL_RGB:
write_red = true;
write_green = true;
write_blue = true;
component_count = 3;
red_offset = 2;
green_offset = 1;
blue_offset = 0;
break;
case GL_RGBA:
write_red = true;
write_green = true;
write_blue = true;
write_alpha = true;
component_count = 4;
red_offset = 3;
green_offset = 2;
blue_offset = 1;
alpha_offset = 0;
break;
case GL_RED:
write_red = true;
component_count = 1;
red_offset = 0;
break;
case GL_GREEN:
write_green = true;
component_count = 1;
green_offset = 0;
break;
case GL_BLUE:
write_blue = true;
component_count = 1;
blue_offset = 0;
break;
case GL_ALPHA:
write_alpha = true;
component_count = 1;
alpha_offset = 0;
break;
}
switch (type) {
case GL_BYTE:
case GL_UNSIGNED_BYTE:
component_size = 1;
break;
case GL_SHORT:
case GL_UNSIGNED_SHORT:
component_size = 2;
break;
case GL_INT:
case GL_UNSIGNED_INT:
case GL_FLOAT:
component_size = 4;
break;
}
char* out_ptr = reinterpret_cast<char*>(pixels);
for (int i = 0; i < (int)height; ++i) {
for (int j = 0; j < (int)width; ++j) {
Gfx::RGBA32 color {};
if (m_current_read_buffer == GL_FRONT || m_current_read_buffer == GL_LEFT || m_current_read_buffer == GL_FRONT_LEFT) {
if (y + i >= m_frontbuffer->width() || x + j >= m_frontbuffer->height())
color = 0;
else
color = m_frontbuffer->scanline(y + i)[x + j];
} else {
color = m_rasterizer.get_backbuffer_pixel(x + j, y + i);
}
float red = ((color >> 24) & 0xff) / 255.0f;
float green = ((color >> 16) & 0xff) / 255.0f;
float blue = ((color >> 8) & 0xff) / 255.0f;
float alpha = (color & 0xff) / 255.0f;
// FIXME: Set up write pointers based on selected endianness (glPixelStore)
red_ptr = out_ptr + (component_size * red_offset);
green_ptr = out_ptr + (component_size * green_offset);
blue_ptr = out_ptr + (component_size * blue_offset);
alpha_ptr = out_ptr + (component_size * alpha_offset);
switch (type) {
case GL_BYTE:
if (write_red)
*reinterpret_cast<GLchar*>(red_ptr) = float_to_i8(red);
if (write_green)
*reinterpret_cast<GLchar*>(green_ptr) = float_to_i8(green);
if (write_blue)
*reinterpret_cast<GLchar*>(blue_ptr) = float_to_i8(blue);
if (write_alpha)
*reinterpret_cast<GLchar*>(alpha_ptr) = float_to_i8(alpha);
break;
case GL_UNSIGNED_BYTE:
if (write_red)
*reinterpret_cast<GLubyte*>(red_ptr) = float_to_u8(red);
if (write_green)
*reinterpret_cast<GLubyte*>(green_ptr) = float_to_u8(green);
if (write_blue)
*reinterpret_cast<GLubyte*>(blue_ptr) = float_to_u8(blue);
if (write_alpha)
*reinterpret_cast<GLubyte*>(alpha_ptr) = float_to_u8(alpha);
break;
case GL_SHORT:
if (write_red)
*reinterpret_cast<GLshort*>(red_ptr) = float_to_i16(red);
if (write_green)
*reinterpret_cast<GLshort*>(green_ptr) = float_to_i16(green);
if (write_blue)
*reinterpret_cast<GLshort*>(blue_ptr) = float_to_i16(blue);
if (write_alpha)
*reinterpret_cast<GLshort*>(alpha_ptr) = float_to_i16(alpha);
break;
case GL_UNSIGNED_SHORT:
if (write_red)
*reinterpret_cast<GLushort*>(red_ptr) = float_to_u16(red);
if (write_green)
*reinterpret_cast<GLushort*>(green_ptr) = float_to_u16(green);
if (write_blue)
*reinterpret_cast<GLushort*>(blue_ptr) = float_to_u16(blue);
if (write_alpha)
*reinterpret_cast<GLushort*>(alpha_ptr) = float_to_u16(alpha);
break;
case GL_INT:
if (write_red)
*reinterpret_cast<GLint*>(red_ptr) = float_to_i32(red);
if (write_green)
*reinterpret_cast<GLint*>(green_ptr) = float_to_i32(green);
if (write_blue)
*reinterpret_cast<GLint*>(blue_ptr) = float_to_i32(blue);
if (write_alpha)
*reinterpret_cast<GLint*>(alpha_ptr) = float_to_i32(alpha);
break;
case GL_UNSIGNED_INT:
if (write_red)
*reinterpret_cast<GLuint*>(red_ptr) = float_to_u32(red);
if (write_green)
*reinterpret_cast<GLuint*>(green_ptr) = float_to_u32(green);
if (write_blue)
*reinterpret_cast<GLuint*>(blue_ptr) = float_to_u32(blue);
if (write_alpha)
*reinterpret_cast<GLuint*>(alpha_ptr) = float_to_u32(alpha);
break;
case GL_FLOAT:
if (write_red)
*reinterpret_cast<GLfloat*>(red_ptr) = min(max(red, 0.0f), 1.0f);
if (write_green)
*reinterpret_cast<GLfloat*>(green_ptr) = min(max(green, 0.0f), 1.0f);
if (write_blue)
*reinterpret_cast<GLfloat*>(blue_ptr) = min(max(blue, 0.0f), 1.0f);
if (write_alpha)
*reinterpret_cast<GLfloat*>(alpha_ptr) = min(max(alpha, 0.0f), 1.0f);
break;
}
out_ptr += component_size * component_count;
}
}
}
void SoftwareGLContext::gl_bind_texture(GLenum target, GLuint texture)
{
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
// FIXME: We only support GL_TEXTURE_2D for now
RETURN_WITH_ERROR_IF(target != GL_TEXTURE_2D, GL_INVALID_ENUM);
if (texture == 0) {
switch (target) {
case GL_TEXTURE_2D:
m_active_texture_unit->unbind_texture(target);
return;
default:
VERIFY_NOT_REACHED();
return;
}
}
auto it = m_allocated_textures.find(texture);
// The texture name does not exist
RETURN_WITH_ERROR_IF(it == m_allocated_textures.end(), GL_INVALID_VALUE);
auto texture_object = it->value;
// Binding a texture to a different target than it was first bound is an invalid operation
// FIXME: We only support GL_TEXTURE_2D for now
RETURN_WITH_ERROR_IF(target == GL_TEXTURE_2D && !texture_object.is_null() && !texture_object->is_texture_2d(), GL_INVALID_OPERATION);
if (!texture_object) {
// This is the first time the texture is bound. Allocate an actual texture object
switch (target) {
case GL_TEXTURE_2D:
texture_object = adopt_ref(*new Texture2D());
break;
default:
VERIFY_NOT_REACHED();
break;
}
m_allocated_textures.set(texture, texture_object);
}
switch (target) {
case GL_TEXTURE_2D:
m_active_texture_unit->bind_texture_to_target(target, texture_object);
break;
}
}
void SoftwareGLContext::gl_active_texture(GLenum texture)
{
RETURN_WITH_ERROR_IF(texture < GL_TEXTURE0 || texture > GL_TEXTURE31, GL_INVALID_ENUM);
m_active_texture_unit = &m_texture_units.at(texture - GL_TEXTURE0);
}
void SoftwareGLContext::gl_get_floatv(GLenum pname, GLfloat* params)
{
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
auto flatten_and_assign_matrix = [¶ms](const FloatMatrix4x4& matrix) {
auto elements = matrix.elements();
for (size_t i = 0; i < 4; ++i) {
for (size_t j = 0; j < 4; ++j) {
params[i * 4 + j] = elements[i][j];
}
}
};
switch (pname) {
case GL_MODELVIEW_MATRIX:
if (m_current_matrix_mode == GL_MODELVIEW)
flatten_and_assign_matrix(m_model_view_matrix);
else {
if (m_model_view_matrix_stack.is_empty())
flatten_and_assign_matrix(FloatMatrix4x4::identity());
else
flatten_and_assign_matrix(m_model_view_matrix_stack.last());
}
break;
default:
// FIXME: Because glQuake only requires GL_MODELVIEW_MATRIX, that is the only parameter
// that we currently support. More parameters should be supported.
RETURN_WITH_ERROR_IF(true, GL_INVALID_ENUM);
}
}
void SoftwareGLContext::gl_get_booleanv(GLenum pname, GLboolean* data)
{
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
switch (pname) {
case GL_BLEND:
*data = m_blend_enabled ? GL_TRUE : GL_FALSE;
break;
case GL_ALPHA_TEST:
*data = m_alpha_test_func ? GL_TRUE : GL_FALSE;
break;
case GL_DEPTH_TEST:
*data = m_depth_test_enabled ? GL_TRUE : GL_FALSE;
break;
case GL_CULL_FACE:
*data = m_cull_faces ? GL_TRUE : GL_FALSE;
break;
default:
// According to the Khronos docs, we always return GL_INVALID_ENUM if we encounter a non-accepted value
// for `pname`
RETURN_WITH_ERROR_IF(true, GL_INVALID_ENUM);
}
}
void SoftwareGLContext::gl_get_integerv(GLenum pname, GLint* data)
{
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
switch (pname) {
case GL_BLEND_SRC_ALPHA:
*data = m_blend_source_factor;
break;
case GL_BLEND_DST_ALPHA:
*data = m_blend_destination_factor;
break;
default:
// According to the Khronos docs, we always return GL_INVALID_ENUM if we encounter a non-accepted value
// for `pname`
RETURN_WITH_ERROR_IF(true, GL_INVALID_ENUM);
}
}
void SoftwareGLContext::gl_depth_mask(GLboolean flag)
{
APPEND_TO_CALL_LIST_AND_RETURN_IF_NEEDED(gl_depth_mask, flag);
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
auto options = m_rasterizer.options();
options.enable_depth_write = (flag != GL_FALSE);
m_rasterizer.set_options(options);
}
void SoftwareGLContext::gl_enable_client_state(GLenum cap)
{
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
switch (cap) {
case GL_VERTEX_ARRAY:
m_client_side_vertex_array_enabled = true;
break;
case GL_COLOR_ARRAY:
m_client_side_color_array_enabled = true;
break;
case GL_TEXTURE_COORD_ARRAY:
m_client_side_texture_coord_array_enabled = true;
break;
default:
RETURN_WITH_ERROR_IF(true, GL_INVALID_ENUM);
}
}
void SoftwareGLContext::gl_disable_client_state(GLenum cap)
{
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
switch (cap) {
case GL_VERTEX_ARRAY:
m_client_side_vertex_array_enabled = false;
break;
case GL_COLOR_ARRAY:
m_client_side_color_array_enabled = false;
break;
case GL_TEXTURE_COORD_ARRAY:
m_client_side_texture_coord_array_enabled = false;
break;
default:
RETURN_WITH_ERROR_IF(true, GL_INVALID_ENUM);
}
}
void SoftwareGLContext::gl_vertex_pointer(GLint size, GLenum type, GLsizei stride, const void* pointer)
{
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
RETURN_WITH_ERROR_IF(!(size == 2 || size == 3 || size == 4), GL_INVALID_VALUE);
RETURN_WITH_ERROR_IF(!(type == GL_SHORT || type == GL_INT || type == GL_FLOAT || type == GL_DOUBLE), GL_INVALID_ENUM);
RETURN_WITH_ERROR_IF(stride < 0, GL_INVALID_VALUE);
m_client_vertex_pointer.size = size;
m_client_vertex_pointer.type = type;
m_client_vertex_pointer.stride = stride;
m_client_vertex_pointer.pointer = pointer;
}
void SoftwareGLContext::gl_color_pointer(GLint size, GLenum type, GLsizei stride, const void* pointer)
{
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
RETURN_WITH_ERROR_IF(!(size == 3 || size == 4), GL_INVALID_VALUE);
RETURN_WITH_ERROR_IF(!(type == GL_BYTE
|| type == GL_UNSIGNED_BYTE
|| type == GL_SHORT
|| type == GL_UNSIGNED_SHORT
|| type == GL_INT
|| type == GL_UNSIGNED_INT
|| type == GL_FLOAT
|| type == GL_DOUBLE),
GL_INVALID_ENUM);
RETURN_WITH_ERROR_IF(stride < 0, GL_INVALID_VALUE);
m_client_color_pointer.size = size;
m_client_color_pointer.type = type;
m_client_color_pointer.stride = stride;
m_client_color_pointer.pointer = pointer;
}
void SoftwareGLContext::gl_tex_coord_pointer(GLint size, GLenum type, GLsizei stride, const void* pointer)
{
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
RETURN_WITH_ERROR_IF(!(size == 1 || size == 2 || size == 3 || size == 4), GL_INVALID_VALUE);
RETURN_WITH_ERROR_IF(!(type == GL_SHORT || type == GL_INT || type == GL_FLOAT || type == GL_DOUBLE), GL_INVALID_ENUM);
RETURN_WITH_ERROR_IF(stride < 0, GL_INVALID_VALUE);
m_client_tex_coord_pointer.size = size;
m_client_tex_coord_pointer.type = type;
m_client_tex_coord_pointer.stride = stride;
m_client_tex_coord_pointer.pointer = pointer;
}
void SoftwareGLContext::gl_draw_arrays(GLenum mode, GLint first, GLsizei count)
{
APPEND_TO_CALL_LIST_AND_RETURN_IF_NEEDED(gl_draw_arrays, mode, first, count);
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
// FIXME: Some modes are still missing (GL_POINTS, GL_LINE_STRIP, GL_LINE_LOOP, GL_LINES,GL_QUAD_STRIP)
RETURN_WITH_ERROR_IF(!(mode == GL_TRIANGLE_STRIP
|| mode == GL_TRIANGLE_FAN
|| mode == GL_TRIANGLES
|| mode == GL_QUADS
|| mode == GL_POLYGON),
GL_INVALID_ENUM);
RETURN_WITH_ERROR_IF(count < 0, GL_INVALID_VALUE);
// At least the vertex array needs to be enabled
if (!m_client_side_vertex_array_enabled)
return;
auto last = first + count;
glBegin(mode);
for (int i = first; i < last; i++) {
if (m_client_side_texture_coord_array_enabled) {
float tex_coords[4] { 0, 0, 0, 0 };
read_from_vertex_attribute_pointer(m_client_tex_coord_pointer, i, tex_coords, false);
glTexCoord4fv(tex_coords);
}
if (m_client_side_color_array_enabled) {
float color[4] { 0, 0, 0, 1 };
read_from_vertex_attribute_pointer(m_client_color_pointer, i, color, true);
glColor4fv(color);
}
float vertex[4] { 0, 0, 0, 1 };
read_from_vertex_attribute_pointer(m_client_vertex_pointer, i, vertex, false);
glVertex4fv(vertex);
}
glEnd();
}
void SoftwareGLContext::gl_draw_elements(GLenum mode, GLsizei count, GLenum type, const void* indices)
{
APPEND_TO_CALL_LIST_AND_RETURN_IF_NEEDED(gl_draw_elements, mode, count, type, indices);
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
// FIXME: Some modes are still missing (GL_POINTS, GL_LINE_STRIP, GL_LINE_LOOP, GL_LINES,GL_QUAD_STRIP)
RETURN_WITH_ERROR_IF(!(mode == GL_TRIANGLE_STRIP
|| mode == GL_TRIANGLE_FAN
|| mode == GL_TRIANGLES
|| mode == GL_QUADS
|| mode == GL_POLYGON),
GL_INVALID_ENUM);
RETURN_WITH_ERROR_IF(!(type == GL_UNSIGNED_BYTE
|| type == GL_UNSIGNED_SHORT
|| type == GL_UNSIGNED_INT),
GL_INVALID_ENUM);
RETURN_WITH_ERROR_IF(count < 0, GL_INVALID_VALUE);
// At least the vertex array needs to be enabled
if (!m_client_side_vertex_array_enabled)
return;
glBegin(mode);
for (int index = 0; index < count; index++) {
int i = 0;
switch (type) {
case GL_UNSIGNED_BYTE:
i = reinterpret_cast<const GLubyte*>(indices)[index];
break;
case GL_UNSIGNED_SHORT:
i = reinterpret_cast<const GLushort*>(indices)[index];
break;
case GL_UNSIGNED_INT:
i = reinterpret_cast<const GLuint*>(indices)[index];
break;
}
if (m_client_side_texture_coord_array_enabled) {
float tex_coords[4] { 0, 0, 0, 0 };
read_from_vertex_attribute_pointer(m_client_tex_coord_pointer, i, tex_coords, false);
glTexCoord4fv(tex_coords);
}
if (m_client_side_color_array_enabled) {
float color[4] { 0, 0, 0, 1 };
read_from_vertex_attribute_pointer(m_client_color_pointer, i, color, true);
glColor4fv(color);
}
float vertex[4] { 0, 0, 0, 1 };
read_from_vertex_attribute_pointer(m_client_vertex_pointer, i, vertex, false);
glVertex4fv(vertex);
}
glEnd();
}
void SoftwareGLContext::gl_depth_range(GLdouble min, GLdouble max)
{
APPEND_TO_CALL_LIST_AND_RETURN_IF_NEEDED(gl_depth_range, min, max);
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
auto options = m_rasterizer.options();
options.depth_min = clamp(min, 0.f, 1.f);
options.depth_max = clamp(max, 0.f, 1.f);
m_rasterizer.set_options(options);
}
void SoftwareGLContext::gl_depth_func(GLenum func)
{
APPEND_TO_CALL_LIST_AND_RETURN_IF_NEEDED(gl_depth_func, func);
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
RETURN_WITH_ERROR_IF(!(func == GL_NEVER
|| func == GL_LESS
|| func == GL_EQUAL
|| func == GL_LEQUAL
|| func == GL_GREATER
|| func == GL_NOTEQUAL
|| func == GL_GEQUAL
|| func == GL_ALWAYS),
GL_INVALID_ENUM);
auto options = m_rasterizer.options();
options.depth_func = func;
m_rasterizer.set_options(options);
}
// General helper function to read arbitrary vertex attribute data into a float array
void SoftwareGLContext::read_from_vertex_attribute_pointer(VertexAttribPointer const& attrib, int index, float* elements, bool normalize)
{
auto byte_ptr = reinterpret_cast<const char*>(attrib.pointer);
size_t stride = attrib.stride;
switch (attrib.type) {
case GL_BYTE: {
if (stride == 0)
stride = sizeof(GLbyte) * attrib.size;
for (int i = 0; i < attrib.size; i++) {
elements[i] = *(reinterpret_cast<const GLbyte*>(byte_ptr + stride * index) + i);
if (normalize)
elements[i] /= 0x80;
}
break;
}
case GL_UNSIGNED_BYTE: {
if (stride == 0)
stride = sizeof(GLubyte) * attrib.size;
for (int i = 0; i < attrib.size; i++) {
elements[i] = *(reinterpret_cast<const GLubyte*>(byte_ptr + stride * index) + i);
if (normalize)
elements[i] /= 0xff;
}
break;
}
case GL_SHORT: {
if (stride == 0)
stride = sizeof(GLshort) * attrib.size;
for (int i = 0; i < attrib.size; i++) {
elements[i] = *(reinterpret_cast<const GLshort*>(byte_ptr + stride * index) + i);
if (normalize)
elements[i] /= 0x8000;
}
break;
}
case GL_UNSIGNED_SHORT: {
if (stride == 0)
stride = sizeof(GLushort) * attrib.size;
for (int i = 0; i < attrib.size; i++) {
elements[i] = *(reinterpret_cast<const GLushort*>(byte_ptr + stride * index) + i);
if (normalize)
elements[i] /= 0xffff;
}
break;
}
case GL_INT: {
if (stride == 0)
stride = sizeof(GLint) * attrib.size;
for (int i = 0; i < attrib.size; i++) {
elements[i] = *(reinterpret_cast<const GLint*>(byte_ptr + stride * index) + i);
if (normalize)
elements[i] /= 0x80000000;
}
break;
}
case GL_UNSIGNED_INT: {
if (stride == 0)
stride = sizeof(GLuint) * attrib.size;
for (int i = 0; i < attrib.size; i++) {
elements[i] = *(reinterpret_cast<const GLuint*>(byte_ptr + stride * index) + i);
if (normalize)
elements[i] /= 0xffffffff;
}
break;
}
case GL_FLOAT: {
if (stride == 0)
stride = sizeof(GLfloat) * attrib.size;
for (int i = 0; i < attrib.size; i++) {
elements[i] = *(reinterpret_cast<const GLfloat*>(byte_ptr + stride * index) + i);
}
break;
}
case GL_DOUBLE: {
if (stride == 0)
stride = sizeof(GLdouble) * attrib.size;
for (int i = 0; i < attrib.size; i++) {
elements[i] = static_cast<float>(*(reinterpret_cast<const GLdouble*>(byte_ptr + stride * index) + i));
}
break;
}
}
}
void SoftwareGLContext::gl_color_mask(GLboolean red, GLboolean green, GLboolean blue, GLboolean alpha)
{
auto options = m_rasterizer.options();
auto mask = options.color_mask;
if (!red)
mask &= ~0x000000ff;
else
mask |= 0x000000ff;
if (!green)
mask &= ~0x0000ff00;
else
mask |= 0x0000ff00;
if (!blue)
mask &= ~0x00ff0000;
else
mask |= 0x00ff0000;
if (!alpha)
mask &= ~0xff000000;
else
mask |= 0xff000000;
options.color_mask = mask;
m_rasterizer.set_options(options);
}
void SoftwareGLContext::gl_polygon_mode(GLenum face, GLenum mode)
{
RETURN_WITH_ERROR_IF(!(face == GL_BACK || face == GL_FRONT || face == GL_FRONT_AND_BACK), GL_INVALID_ENUM);
RETURN_WITH_ERROR_IF(!(mode == GL_POINT || mode == GL_LINE || mode == GL_FILL), GL_INVALID_ENUM);
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
auto options = m_rasterizer.options();
options.polygon_mode = mode;
m_rasterizer.set_options(options);
}
void SoftwareGLContext::gl_fogfv(GLenum pname, GLfloat* params)
{
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
auto options = m_rasterizer.options();
switch (pname) {
case GL_FOG_COLOR:
// Set rasterizer options fog color
// NOTE: We purposefully don't check for `nullptr` here (as with other calls). The spec states nothing
// about us checking for such things. If the programmer does so and hits SIGSEGV, that's on them.
options.fog_color = FloatVector4 { params[0], params[1], params[2], params[3] };
break;
default:
RETURN_WITH_ERROR_IF(true, GL_INVALID_ENUM);
}
m_rasterizer.set_options(options);
}
void SoftwareGLContext::gl_fogf(GLenum pname, GLfloat param)
{
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
RETURN_WITH_ERROR_IF(param < 0.0f, GL_INVALID_VALUE);
auto options = m_rasterizer.options();
switch (pname) {
case GL_FOG_DENSITY:
options.fog_density = param;
break;
default:
RETURN_WITH_ERROR_IF(true, GL_INVALID_ENUM);
}
m_rasterizer.set_options(options);
}
void SoftwareGLContext::gl_fogi(GLenum pname, GLint param)
{
RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
RETURN_WITH_ERROR_IF(!(param == GL_EXP || param == GL_EXP2 || param != GL_LINEAR), GL_INVALID_ENUM);
auto options = m_rasterizer.options();
switch (pname) {
case GL_FOG_MODE:
options.fog_mode = param;
break;
default:
RETURN_WITH_ERROR_IF(true, GL_INVALID_ENUM);
}
m_rasterizer.set_options(options);
}
void SoftwareGLContext::gl_pixel_store(GLenum pname, GLfloat param)
{
// FIXME: Implement missing parameters
switch (pname) {
case GL_UNPACK_ROW_LENGTH:
RETURN_WITH_ERROR_IF(param < 0, GL_INVALID_VALUE);
m_unpack_row_length = static_cast<size_t>(param);
break;
default:
RETURN_WITH_ERROR_IF(true, GL_INVALID_ENUM);
break;
}
}
void SoftwareGLContext::present()
{
m_rasterizer.blit_to(*m_frontbuffer);
}
}