4coder/4ed_rendering.cpp

506 lines
16 KiB
C++

/*
* Mr. 4th Dimention - Allen Webster
*
* 12.17.2014
*
* Rendering layer for project codename "4ed"
*
*/
// TOP
inline void
draw_set_clip(Render_Target *target, i32_Rect clip_box){
glScissor(clip_box.x0,
target->height - clip_box.y1,
clip_box.x1 - clip_box.x0,
clip_box.y1 - clip_box.y0);
}
inline void
draw_bind_texture(Render_Target *target, i32 texid){
if (target->bound_texture != texid){
glBindTexture(GL_TEXTURE_2D, texid);
target->bound_texture = texid;
}
}
inline void
draw_set_color(Render_Target *target, u32 color){
if (target->color != color){
target->color = color;
Vec4 c = unpack_color4(color);
glColor4f(c.r, c.g, c.b, c.a);
}
}
inline void
draw_safe_push(Render_Target *target, i32 size, void *x){
if (size + target->size <= target->max){
memcpy(target->push_buffer + target->size, x, size);
target->size += size;
}
}
#define PutStruct(s,x) draw_safe_push(target, sizeof(s), &x)
internal void
draw_push_piece(Render_Target *target, Render_Piece_Combined piece){
PutStruct(Render_Piece_Header, piece.header);
switch (piece.header.type){
case piece_type_rectangle:
case piece_type_outline:
PutStruct(Render_Piece_Rectangle, piece.rectangle);
break;
case piece_type_gradient:
PutStruct(Render_Piece_Gradient, piece.gradient);
break;
case piece_type_glyph:
case piece_type_mono_glyph:
PutStruct(Render_Piece_Glyph, piece.glyph);
break;
case piece_type_mono_glyph_advance:
PutStruct(Render_Piece_Glyph_Advance, piece.glyph_advance);
break;
}
Assert(target->size <= target->max);
}
internal void
draw_push_piece_clip(Render_Target *target, i32_Rect clip_box){
// TODO(allen): optimize out if there are two clip box changes in a row
Render_Piece_Change_Clip clip;
Render_Piece_Header header;
header.type = piece_type_change_clip;
clip.box = clip_box;
PutStruct(Render_Piece_Header, header);
PutStruct(Render_Piece_Change_Clip, clip);
}
internal void
draw_push_clip(Render_Target *target, i32_Rect clip_box){
Assert(target->clip_top == -1 ||
fits_inside(clip_box, target->clip_boxes[target->clip_top]));
Assert(target->clip_top+1 < ArrayCount(target->clip_boxes));
target->clip_boxes[++target->clip_top] = clip_box;
draw_push_piece_clip(target, clip_box);
}
internal i32_Rect
draw_pop_clip(Render_Target *target){
i32_Rect result = {0};
i32_Rect clip_box = {0};
Assert(target->clip_top > 0);
result = target->clip_boxes[target->clip_top];
--target->clip_top;
clip_box = target->clip_boxes[target->clip_top];
draw_push_piece_clip(target, clip_box);
return(result);
}
#define ExtractStruct(s) ((s*)cursor); cursor += sizeof(s)
inline void
private_draw_rectangle(Render_Target *target, f32_Rect rect, u32 color){
draw_set_color(target, color);
draw_bind_texture(target, 0);
glBegin(GL_QUADS);
{
glVertex2f(rect.x0, rect.y0);
glVertex2f(rect.x0, rect.y1);
glVertex2f(rect.x1, rect.y1);
glVertex2f(rect.x1, rect.y0);
}
glEnd();
}
inline void
private_draw_rectangle_outline(Render_Target *target, f32_Rect rect, u32 color){
f32_Rect r;
r.x0 = rect.x0 + .5f;
r.y0 = rect.y0 + .5f;
r.x1 = rect.x1 - .5f;
r.y1 = rect.y1 - .5f;
draw_set_color(target, color);
draw_bind_texture(target, 0);
glBegin(GL_LINE_STRIP);
{
glVertex2f(r.x0, r.y0);
glVertex2f(r.x1, r.y0);
glVertex2f(r.x1, r.y1);
glVertex2f(r.x0, r.y1);
glVertex2f(r.x0, r.y0);
}
glEnd();
}
inline void
private_draw_gradient(Render_Target *target, f32_Rect rect,
Vec4 color_left, Vec4 color_right){
Vec4 cl = color_left;
Vec4 cr = color_right;
draw_bind_texture(target, 0);
glBegin(GL_QUADS);
{
glColor4f(cl.r, cl.g, cl.b, cl.a);
glVertex2f(rect.x0, rect.y0);
glVertex2f(rect.x0, rect.y1);
glColor4f(cr.r, cr.g, cr.b, cr.a);
glVertex2f(rect.x1, rect.y1);
glVertex2f(rect.x1, rect.y0);
}
glEnd();
}
struct Render_Quad{
f32 x0, y0, x1, y1;
f32 s0, t0, s1, t1;
};
inline Render_Quad
get_render_quad(Glyph_Data *b, int pw, int ph, float xpos, float ypos){
Render_Quad q;
float ipw = 1.0f / pw, iph = 1.0f / ph;
q.x0 = xpos + b->xoff;
q.y0 = ypos + b->yoff;
q.x1 = xpos + b->xoff2;
q.y1 = ypos + b->yoff2;
q.s0 = b->x0 * ipw;
q.t0 = b->y0 * iph;
q.s1 = b->x1 * ipw;
q.t1 = b->y1 * iph;
return(q);
}
inline Render_Quad
get_exact_render_quad(Glyph_Data *b, int pw, int ph, float xpos, float ypos){
Render_Quad q;
float ipw = 1.0f / pw, iph = 1.0f / ph;
q.x0 = xpos;
q.y0 = ypos + b->yoff;
q.x1 = xpos + (b->xoff2 - b->xoff);
q.y1 = ypos + b->yoff2;
q.s0 = b->x0 * ipw;
q.t0 = b->y0 * iph;
q.s1 = b->x1 * ipw;
q.t1 = b->y1 * iph;
return(q);
}
inline void
private_draw_glyph(Render_Target *target, Render_Font *font,
u8 character, f32 x, f32 y, u32 color){
Render_Quad q = get_render_quad(
font->glyphs + character,
font->tex_width, font->tex_height, x, y
);
draw_set_color(target, color);
draw_bind_texture(target, font->tex);
glBegin(GL_QUADS);
{
glTexCoord2f(q.s0, q.t1); glVertex2f(q.x0, q.y1);
glTexCoord2f(q.s1, q.t1); glVertex2f(q.x1, q.y1);
glTexCoord2f(q.s1, q.t0); glVertex2f(q.x1, q.y0);
glTexCoord2f(q.s0, q.t0); glVertex2f(q.x0, q.y0);
}
glEnd();
}
inline void
private_draw_glyph_mono(Render_Target *target, Render_Font *font, u8 character,
f32 x, f32 y, f32 advance, u32 color){
f32 left = font->glyphs[character].x0;
f32 right = font->glyphs[character].x1;
f32 width = (right - left);
f32 x_shift = (advance - width) * .5f;
x += x_shift;
Render_Quad q = get_exact_render_quad(
font->glyphs + character,
font->tex_width, font->tex_height, x, y
);
draw_set_color(target, color);
draw_bind_texture(target, font->tex);
glBegin(GL_QUADS);
{
glTexCoord2f(q.s0, q.t1); glVertex2f(q.x0, q.y1);
glTexCoord2f(q.s1, q.t1); glVertex2f(q.x1, q.y1);
glTexCoord2f(q.s1, q.t0); glVertex2f(q.x1, q.y0);
glTexCoord2f(q.s0, q.t0); glVertex2f(q.x0, q.y0);
}
glEnd();
}
inline void
private_draw_glyph_mono(Render_Target *target, Render_Font *font, u8 character,
real32 x, real32 y, u32 color){
private_draw_glyph_mono(target, font, character, x, y, (f32)font->advance, color);
}
internal void
launch_rendering(Render_Target *target){
byte *cursor = target->push_buffer;
byte *cursor_end = cursor + target->size;
for (; cursor < cursor_end;){
Render_Piece_Header *header = ExtractStruct(Render_Piece_Header);
i32 type = header->type;
switch (type){
case piece_type_rectangle:
{
Render_Piece_Rectangle *rectangle =
ExtractStruct(Render_Piece_Rectangle);
private_draw_rectangle(target, rectangle->rect, rectangle->color);
}break;
case piece_type_outline:
{
Render_Piece_Rectangle *rectangle =
ExtractStruct(Render_Piece_Rectangle);
private_draw_rectangle_outline(target, rectangle->rect, rectangle->color);
}break;
case piece_type_gradient:
{
Render_Piece_Gradient *gradient =
ExtractStruct(Render_Piece_Gradient);
private_draw_gradient(target, gradient->rect,
unpack_color4(gradient->left_color),
unpack_color4(gradient->right_color));
}break;
case piece_type_glyph:
{
Render_Piece_Glyph *glyph =
ExtractStruct(Render_Piece_Glyph);
Render_Font *font = get_font_info(&target->font_set, glyph->font_id)->font;
if (font)
private_draw_glyph(target, font, glyph->character,
glyph->pos.x, glyph->pos.y, glyph->color);
}break;
case piece_type_mono_glyph:
{
Render_Piece_Glyph *glyph =
ExtractStruct(Render_Piece_Glyph);
Render_Font *font = get_font_info(&target->font_set, glyph->font_id)->font;
if (font)
private_draw_glyph_mono(target, font, glyph->character,
glyph->pos.x, glyph->pos.y, glyph->color);
}break;
case piece_type_mono_glyph_advance:
{
Render_Piece_Glyph_Advance *glyph =
ExtractStruct(Render_Piece_Glyph_Advance);
Render_Font *font = get_font_info(&target->font_set, glyph->font_id)->font;
if (font)
private_draw_glyph_mono(target, font, glyph->character,
glyph->pos.x, glyph->pos.y,
glyph->advance, glyph->color);
}break;
case piece_type_change_clip:
{
Render_Piece_Change_Clip *clip =
ExtractStruct(Render_Piece_Change_Clip);
draw_set_clip(target, clip->box);
}break;
}
}
}
#undef ExtractStruct
internal void*
part_alloc(int size, void *context){
Partition *part = (Partition*)context;
void *result = push_block(part, size);
return(result);
}
internal void
part_free(void *ptr, void *context){
}
#define STBTT_malloc part_alloc
#define STBTT_free part_free
#define STB_TRUETYPE_IMPLEMENTATION
#include "stb_truetype.h"
// TODO(allen): Put the burden of translation outside
// of this function (and other functions implementing
// the same interface).
internal i32
draw_font_load(Partition *part,
Render_Font *font_out,
char *filename_untranslated,
i32 pt_size,
i32 tab_width,
i32 oversample,
b32 store_texture){
char space_[1024];
String filename = make_fixed_width_string(space_);
b32 translate_success = sysshared_to_binary_path(&filename, filename_untranslated);
if (!translate_success) return 0;
i32 result = 1;
stbtt_packedchar chardata[256];
File_Data file = sysshared_load_file(filename.str);
if (!file.data.data){
result = 0;
}
else{
stbtt_fontinfo font;
if (!stbtt_InitFont(&font, (u8*)file.data.data, 0)){
result = 0;
}
else{
memset(font_out, 0, sizeof(*font_out));
i32 ascent, descent, line_gap;
stbtt_GetFontVMetrics(&font, &ascent, &descent, &line_gap);
f32 scale = stbtt_ScaleForPixelHeight(&font, (f32)pt_size);
f32 scaled_ascent = scale*ascent;
f32 scaled_descent = scale*descent;
f32 scaled_line_gap = scale*line_gap;
font_out->height = (i32)(scaled_ascent - scaled_descent + scaled_line_gap);
font_out->ascent = (i32)(scaled_ascent);
font_out->descent = (i32)(scaled_descent);
font_out->line_skip = (i32)(scaled_line_gap);
if (store_texture){
Temp_Memory temp = begin_temp_memory(part);
i32 tex_width = pt_size*16*oversample;
i32 tex_height = pt_size*16*oversample;
void *block = sysshared_push_block(part, tex_width * tex_height);
font_out->tex_width = tex_width;
font_out->tex_height = tex_height;
/////////////////////////////////////////////////////////////////
stbtt_pack_context spc;
if (stbtt_PackBegin(&spc, (u8*)block, tex_width, tex_height,
tex_width, 1, part)){
stbtt_PackSetOversampling(&spc, oversample, oversample);
if (!stbtt_PackFontRange(&spc, (u8*)file.data.data, 0,
STBTT_POINT_SIZE((f32)pt_size),
0, 128, chardata)){
result = 0;
}
stbtt_PackEnd(&spc);
}
else{
result = 0;
}
/////////////////////////////////////////////////////////////////
if (result){
GLuint font_tex;
glGenTextures(1, &font_tex);
glBindTexture(GL_TEXTURE_2D, font_tex);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexImage2D(GL_TEXTURE_2D, 0, GL_ALPHA, tex_width, tex_height, 0, GL_ALPHA, GL_UNSIGNED_BYTE, block);
font_out->tex = font_tex;
glBindTexture(GL_TEXTURE_2D, 0);
f32 *advance_data = font_out->advance_data;
Glyph_Data *glyphs = font_out->glyphs;
for (u8 code_point = 0; code_point < 128; ++code_point){
advance_data[code_point] = (f32)(CEIL32(chardata[code_point].xadvance));
glyphs[code_point].x0 = chardata[code_point].x0;
glyphs[code_point].y0 = chardata[code_point].y0;
glyphs[code_point].x1 = chardata[code_point].x1;
glyphs[code_point].y1 = chardata[code_point].y1;
glyphs[code_point].xoff = chardata[code_point].xoff;
glyphs[code_point].yoff = chardata[code_point].yoff + font_out->ascent;
glyphs[code_point].xoff2 = chardata[code_point].xoff2;
glyphs[code_point].yoff2 = chardata[code_point].yoff2 + font_out->ascent;
}
glyphs['\r'] = glyphs[' '];
advance_data['\r'] = advance_data[' '];
glyphs['\n'] = glyphs[' '];
advance_data['\n'] = advance_data[' '];
glyphs['\t'] = glyphs[' '];
advance_data['\t'] = advance_data[' ']*tab_width;
i32 max_advance = 0;
for (u8 code_point = 0; code_point < 128; ++code_point){
if (stbtt_FindGlyphIndex(&font, code_point) != 0){
font_out->glyphs[code_point].exists = 1;
i32 advance = CEIL32(advance_data[code_point]);
if (max_advance < advance){
max_advance = advance;
}
}
}
font_out->advance = max_advance - 1;
}
end_temp_memory(temp);
}
}
system_free_memory(file.data.data);
}
return(result);
}
internal
Release_Font_Sig(draw_release_font){
glDeleteTextures(1, &font->tex);
font->tex = 0;
}
// BOTTOM