4coder/opengl/4ed_opengl_render.cpp

412 lines
15 KiB
C++

/*
* Mr. 4th Dimention - Allen Webster
*
* 10.11.2017
*
* OpenGL render implementation
*
*/
// TOP
//#define GL_FUNC(N,R,P) typedef R (N##_Function) P; N##_Function *P = 0;
//#include "4ed_opengl_funcs.h"
#include "4ed_opengl_defines.h"
#if 0
internal GLuint
gl__texture_initialize(GLint tex_width, GLint tex_height, u32 *pixels){
GLuint tex;
glGenTextures(1, &tex);
glBindTexture(GL_TEXTURE_2D, tex);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAX_LEVEL, 0);
glTexImage2D(GL_TEXTURE_2D, 0, GL_R8, tex_width, tex_height, 0, GL_RED, GL_UNSIGNED_INT, pixels);
return(tex);
}
#endif
internal u32
gl__get_gpu_texture(Vec3_i32 dim, Texture_Kind texture_kind){
u32 tex;
glGenTextures(1, &tex);
glBindTexture(GL_TEXTURE_2D, tex);
glTexParameteri(GL_TEXTURE_2D_ARRAY, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D_ARRAY, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D_ARRAY, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D_ARRAY, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D_ARRAY, GL_TEXTURE_MAX_LEVEL, 0);
glTexStorage3D(GL_TEXTURE_2D_ARRAY, 0, GL_R8, dim.x, dim.y, 0, GL_RED, GL_UNSIGNED_INT, 0);
return(tex);
}
internal void
gl__draw_bind_texture(Render_Target *t, i32 texid){
if (t->bound_texture != texid){
glBindTexture(GL_TEXTURE_2D, texid);
t->bound_texture = texid;
}
}
internal void CALL_CONVENTION
gl__error_callback(GLenum source, GLenum type, GLuint id, GLenum severity, GLsizei length, char *message, void *userParam){
InvalidPath;
}
char *gl__header = R"foo(#version 150
)foo";
char *gl__vertex = R"foo(
uniform vec2 view_t;
uniform mat2x2 view_m;
uniform vec4 color;
in vec2 vertex_p;
in vec2 vertex_t;
smooth out vec4 fragment_color;
smooth out vec2 uv;
void main(void)
{
gl_Position = vec4(view_m*(vertex_p - view_t), 0.f, 1.f);
fragment_color = color;
uv = vertex_t;
}
)foo";
char *gl__fragment = R"foo(
smooth in vec4 fragment_color;
smooth in vec2 uv;
uniform sampler2D sampler;
uniform float texture_override;
out vec4 out_color;
void main(void)
{
out_color = fragment_color*(texture(sampler, uv).r + texture_override);
}
)foo";
#define AttributeList(X) \
X(vertex_p) \
X(vertex_t)
#define UniformList(X) \
X(view_t) \
X(view_m) \
X(color) \
X(sampler) \
X(texture_override)
struct GL_Program{
u32 program;
#define GetAttributeLocation(N) i32 N;
AttributeList(GetAttributeLocation)
#undef GetAttributeLocation
#define GetUniformLocation(N) i32 N;
UniformList(GetUniformLocation)
#undef GetUniformLocation
};
internal GL_Program
gl__make_program(char *header, char *vertex, char *fragment){
if (header == 0){
header = "";
}
GLuint vertex_shader = glCreateShader(GL_VERTEX_SHADER);
GLchar *vertex_source_array[] = { header, vertex };
glShaderSource(vertex_shader, ArrayCount(vertex_source_array), vertex_source_array, 0);
glCompileShader(vertex_shader);
GLuint fragment_shader = glCreateShader(GL_FRAGMENT_SHADER);
GLchar *fragment_source_array[] = { header, fragment };
glShaderSource(fragment_shader, ArrayCount(fragment_source_array), fragment_source_array, 0);
glCompileShader(fragment_shader);
GLuint program = glCreateProgram();
glAttachShader(program, vertex_shader);
glAttachShader(program, fragment_shader);
glLinkProgram(program);
glValidateProgram(program);
GLint success = false;
glGetProgramiv(program, GL_LINK_STATUS, &success);
if (!success){
GLsizei ignore = 0;
char vertex_errors[KB(4)];
char fragment_errors[KB(4)];
char program_errors[KB(4)];
glGetShaderInfoLog(vertex_shader, sizeof(vertex_errors), &ignore, vertex_errors);
glGetShaderInfoLog(fragment_shader, sizeof(fragment_errors), &ignore, fragment_errors);
glGetProgramInfoLog(program, sizeof(program_errors), &ignore, program_errors);
#if SHIP_MODE
os_popup_window(string_u8_litexpr("Error"), string_u8_litexpr("Shader compilation failed."));
#endif
InvalidPath;
}
glDeleteShader(vertex_shader);
glDeleteShader(fragment_shader);
GL_Program result = {};
result.program = program;
#define GetAttributeLocation(N) result.N = glGetAttribLocation(program, #N);
AttributeList(GetAttributeLocation)
#undef GetAttributeLocation
#define GetUniformLocation(N) result.N = glGetUniformLocation(program, #N);
UniformList(GetUniformLocation)
#undef GetUniformLocation
return(result);
}
#define GLOffset(p,m) ((void*)(OffsetOfMemberStruct(p,m)))
internal void
gl_render(Render_Target *t, Arena *scratch){
local_persist b32 first_opengl_call = true;
local_persist u32 attribute_buffer = 0;
local_persist GL_Program gpu_program = {};
if (first_opengl_call){
first_opengl_call = false;
#if !SHIP_MODE
glEnable(GL_DEBUG_OUTPUT_SYNCHRONOUS);
glDebugMessageControl(GL_DONT_CARE, GL_DONT_CARE, GL_DEBUG_SEVERITY_NOTIFICATION, 0, 0, true);
glDebugMessageControl(GL_DONT_CARE, GL_DONT_CARE, GL_DEBUG_SEVERITY_LOW, 0, 0, true);
glDebugMessageControl(GL_DONT_CARE, GL_DONT_CARE, GL_DEBUG_SEVERITY_MEDIUM, 0, 0, true);
glDebugMessageControl(GL_DONT_CARE, GL_DONT_CARE, GL_DEBUG_SEVERITY_HIGH, 0, 0, true);
glDebugMessageCallback(gl__error_callback, 0);
#endif
////////////////////////////////
GLuint dummy_vao = 0;
glGenVertexArrays(1, &dummy_vao);
glBindVertexArray(dummy_vao);
////////////////////////////////
glGenBuffers(1, &attribute_buffer);
glBindBuffer(GL_ARRAY_BUFFER, attribute_buffer);
////////////////////////////////
glEnable(GL_SCISSOR_TEST);
glEnable(GL_BLEND);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
////////////////////////////////
gpu_program = gl__make_program(gl__header, gl__vertex, gl__fragment);
glUseProgram(gpu_program.program);
}
i32 width = t->width;
i32 height = t->height;
glViewport(0, 0, width, height);
glScissor(0, 0, width, height);
glClearColor(1.f, 0.f, 1.f, 1.f);
glClear(GL_COLOR_BUFFER_BIT);
glBindTexture(GL_TEXTURE_2D, 0);
t->bound_texture = 0;
for (Render_Free_Texture *free_texture = t->free_texture_first;
free_texture != 0;
free_texture = free_texture->next){
glDeleteTextures(1, &free_texture->tex_id);
}
t->free_texture_first = 0;
t->free_texture_last = 0;
u8 *start = (u8*)t->buffer.base;
u8 *end = (u8*)t->buffer.base + t->buffer.pos;
Render_Command_Header *header = 0;
for (u8 *p = start; p < end; p += header->size){
header = (Render_Command_Header*)p;
i32 type = header->type;
switch (type){
case RenCom_Rectangle:
{
Render_Command_Rectangle *rectangle = (Render_Command_Rectangle*)header;
gl__draw_bind_texture(t, 0);
Vec4 c = unpack_color4(rectangle->color);
i32 vertex_count = ArrayCount(rectangle->vertices);
glBufferData(GL_ARRAY_BUFFER, sizeof(rectangle->vertices), rectangle->vertices, GL_STREAM_DRAW);
glEnableVertexAttribArray(gpu_program.vertex_p);
glVertexAttribPointer(gpu_program.vertex_p, 2, GL_FLOAT, true, sizeof(rectangle->vertices[0]), 0);
glUniform2f(gpu_program.view_t, width/2.f, height/2.f);
f32 m[4] = {
2.f/width, 0.f,
0.f, -2.f/height,
};
glUniformMatrix2fv(gpu_program.view_m, 1, GL_FALSE, m);
glUniform4f(gpu_program.color, c.r, c.g, c.b, c.a);
glUniform1f(gpu_program.texture_override, 1.f);
glDrawArrays(GL_TRIANGLE_STRIP, 0, vertex_count);
glDisableVertexAttribArray(gpu_program.vertex_p);
}break;
case RenCom_Glyph:
{
Render_Command_Glyph *glyph = (Render_Command_Glyph*)header;
#if 0
Font_Pointers font = system_font_get_pointers_by_id(glyph->font_id);
if (!font.valid){
break;
}
#endif
Face *face = 0;
if (face == 0){
break;
}
u32 codepoint = glyph->codepoint;
#if 0
u32 page_number = codepoint/GLYPHS_PER_PAGE;
Glyph_Page *page = font_cached_get_page(font.pages, page_number);
if (page == 0){
break;
}
if (!page->has_gpu_setup){
Temp_Memory temp = begin_temp(scratch);
i32 tex_width = 0;
i32 tex_height = 0;
u32 *pixels = font_load_page_pixels(scratch, font.settings, page, page_number, &tex_width, &tex_height);
page->has_gpu_setup = true;
page->gpu_tex = gl__texture_initialize(tex_width, tex_height, pixels);
end_temp(temp);
}
if (page->gpu_tex == 0){
break;
}
u32 glyph_index = codepoint%GLYPHS_PER_PAGE;
Glyph_Bounds bounds = page->glyphs[glyph_index];
GLuint tex = page->gpu_tex;
i32 tex_width = page->tex_width;
i32 tex_height = page->tex_height;
// TODO(allen): do(think about baking unit_u/unit_v into font data)
f32 unit_u = 1.f/tex_width;
f32 unit_v = 1.f/tex_height;
#else
u16 glyph_index = 0;
if (!table_read(&face->codepoint_to_index_table, codepoint, &glyph_index)){
glyph_index = 0;
}
Glyph_Bounds bounds = face->bounds[glyph_index];
GLuint tex = face->gpu_texture;
Vec3_f32 gpu_texture_dim = face->gpu_texture_dim;
#endif
f32 x = glyph->pos.x;
f32 y = glyph->pos.y;
f32_Rect uv = Rf32(bounds.uv.x0, bounds.uv.y0,
bounds.uv.x1, bounds.uv.y1);
f32_Rect xy = Rf32(x + bounds.xy_off.x0, y + bounds.xy_off.y0,
x + bounds.xy_off.x1, y + bounds.xy_off.y1);
struct Textutred_Vertex{
Vec2 xy;
Vec2 uv;
};
Textutred_Vertex vertices[4];
if (!HasFlag(glyph->flags, GlyphFlag_Rotate90)){
vertices[0].xy = V2(xy.x0, xy.y1); vertices[0].uv = V2(uv.x0, uv.y1);
vertices[1].xy = V2(xy.x1, xy.y1); vertices[1].uv = V2(uv.x1, uv.y1);
vertices[2].xy = V2(xy.x0, xy.y0); vertices[2].uv = V2(uv.x0, uv.y0);
vertices[3].xy = V2(xy.x1, xy.y0); vertices[3].uv = V2(uv.x1, uv.y0);
}
else{
vertices[0].xy = V2(xy.x0, xy.y1); vertices[0].uv = V2(uv.x1, uv.y1);
vertices[1].xy = V2(xy.x1, xy.y1); vertices[1].uv = V2(uv.x1, uv.y0);
vertices[2].xy = V2(xy.x0, xy.y0); vertices[2].uv = V2(uv.x0, uv.y1);
vertices[3].xy = V2(xy.x1, xy.y0); vertices[3].uv = V2(uv.x0, uv.y0);
}
gl__draw_bind_texture(t, tex);
Vec4 c = unpack_color4(glyph->color);
i32 vertex_count = ArrayCount(vertices);
glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STREAM_DRAW);
glEnableVertexAttribArray(gpu_program.vertex_p);
glEnableVertexAttribArray(gpu_program.vertex_t);
glVertexAttribPointer(gpu_program.vertex_p, 2, GL_FLOAT, true, sizeof(vertices[0]), GLOffset(&vertices[0], xy));
glVertexAttribPointer(gpu_program.vertex_t, 2, GL_FLOAT, true, sizeof(vertices[0]), GLOffset(&vertices[0], uv));
glUniform2f(gpu_program.view_t, width/2.f, height/2.f);
f32 m[4] = {
2.f/width, 0.f,
0.f, -2.f/height,
};
glUniformMatrix2fv(gpu_program.view_m, 1, GL_FALSE, m);
glUniform4f(gpu_program.color, c.r, c.g, c.b, c.a);
glUniform1i(gpu_program.sampler, 0);
glUniform1f(gpu_program.texture_override, 0.f);
glDrawArrays(GL_TRIANGLE_STRIP, 0, vertex_count);
glDisableVertexAttribArray(gpu_program.vertex_p);
glDisableVertexAttribArray(gpu_program.vertex_t);
#if 0
if (codepoint != ' ' && font.settings->parameters.underline){
// TODO(allen): recover this feature
glDisable(GL_TEXTURE_2D);
f32 x0 = x;
f32 x1 = x + page->advance[glyph_index];
f32 yoff1 = y + font.metrics->underline_yoff1;
f32 yoff2 = y + font.metrics->underline_yoff2;
glBegin(GL_QUADS);
{
glVertex2f(x0, yoff1);
glVertex2f(x1, yoff1);
glVertex2f(x1, yoff2);
glVertex2f(x0, yoff2);
}
glEnd();
glEnable(GL_TEXTURE_2D);
}
#endif
}break;
case RenCom_ChangeClip:
{
Render_Command_Change_Clip *clip = (Render_Command_Change_Clip*)header;
i32_Rect box = clip->box;
glScissor(box.x0, height - box.y1, box.x1 - box.x0, box.y1 - box.y0);
}break;
}
}
if (target.out_of_memory){
glScissor(0, 0, width, height);
glClearColor(0.f, 1.f, 0.f, 1.f);
glClear(GL_COLOR_BUFFER_BIT);
target.out_of_memory = false;
}
glFlush();
}
// BOTTOM