master
Alessandro Mauri 1 year ago
parent 4939fd7068
commit 884d5a1987
Signed by: alema
GPG Key ID: 2B7BF9531FF03BE8
  1. 11
      text_rendering/font_vertshader.glsl
  2. 13
      text_rendering/main.c
  3. 176
      text_rendering/ren.c
  4. BIN
      text_rendering/test
  5. 4
      text_rendering/util.c

@ -13,11 +13,14 @@ out vec2 uv;
void main()
{
vec4 pos = vec4(position.x, position.y, 0.0f, 1.0f);
vec2 hsize = vec2(float(viewsize.x)/2.0f, float(viewsize.y)/2.0f);
// matrix to change from image coordinates to opengl coordinates
mat2 transform = mat2(vec2(0.0f, -1.0f), vec2(1.0f, 0.0f));
vec2 v = vec2(float(viewsize.x), float(viewsize.y));
vec2 h = v/2.0f;
vec2 p = ((position-h)/ h);
pos.xy = (pos.xy - hsize) / hsize;
vec4 pos = vec4(p.x, p.y, 0.0f, 1.0f);
gl_Position = pos;
uv = txcoord / float(texturesize);
uv = vec2(txcoord.x / float(texturesize.x), (float(texturesize.y) - txcoord.y) / float(texturesize.y));
}

@ -1,5 +1,6 @@
#include <SDL2/SDL.h>
#include <SDL2/SDL_events.h>
#include <SDL2/SDL_video.h>
#include <stdlib.h>
#include <stdio.h>
@ -29,6 +30,18 @@ int main(void)
SDL_WaitEvent(&e);
if (e.type == SDL_QUIT)
break;
if (e.type == SDL_WINDOWEVENT) {
switch (e.window.event) {
case SDL_WINDOWEVENT_RESIZED:
case SDL_WINDOWEVENT_SIZE_CHANGED:
ren_update_viewport(e.window.data1, e.window.data2);
case SDL_WINDOWEVENT_EXPOSED:
ren_render_text("ciao mamma", 0, 0, 100, 100, 12);
SDL_GL_SwapWindow(win);
break;
default: break;
}
}
}
ren_free();

@ -10,6 +10,10 @@
#include "ren.h"
#define GLERR() {int a = glGetError(); if (a != GL_NO_ERROR) printf("(%s:%d %s) glError: 0x%x %s\n", __FILE__, __LINE__, __func__, a, glerr[a]);}
#define GL(f) f; GLERR()
enum REN_ERR {
REN_SUCCESS = 0,
REN_ERRNO,
@ -47,11 +51,12 @@ const char * ren_err_msg[] = {
};
#define ELEM(x) [x] = #x,
#define ELEM(x...) [x] = #x,
const char *glerr[] = {
ELEM(GL_INVALID_ENUM)
ELEM(GL_INVALID_VALUE)
ELEM(GL_INVALID_OPERATION)
ELEM(GL_OUT_OF_MEMORY)
};
#undef ELEM
@ -135,11 +140,11 @@ static GLuint shader_compile(const char *shader, GLuint type)
{
GLuint s;
// initialize the vertex shader and get the corresponding id
s = glCreateShader(type);
s = GL(glCreateShader(type))
if (!s) REN_RET(0, REN_VERTEX)
// get the shader into opengl
glShaderSource(s, 1, &shader, NULL);
glCompileShader(s);
GL(glShaderSource(s, 1, &shader, NULL))
GL(glCompileShader(s))
if (shader_compile_error(s))
REN_RET(0, REN_COMPILE)
return s;
@ -179,21 +184,21 @@ static GLuint ren_compile_program(const char *vs_path, const char *fs_path)
// create the main program object, it is an amalgamation of all shaders
prog = glCreateProgram();
prog = GL(glCreateProgram())
if (!prog) REN_RET(0, REN_PROGRAM)
// attach the shaders to the program (set which shaders are present)
glAttachShader(prog, gl_vertshader);
glAttachShader(prog, gl_fragshader);
GL(glAttachShader(prog, gl_vertshader))
GL(glAttachShader(prog, gl_fragshader))
// then link the program (basically the linking stage of the program)
glLinkProgram(prog);
GL(glLinkProgram(prog))
if (shader_link_error(prog))
REN_RET(0, REN_LINK)
// after linking the shaders can be detached and the source freed from
// memory since the program is ready to use
glDetachShader(prog, gl_vertshader);
glDetachShader(prog, gl_fragshader);
GL(glDetachShader(prog, gl_vertshader))
GL(glDetachShader(prog, gl_fragshader))
return prog;
}
@ -206,16 +211,16 @@ static GLuint ren_texturergb_2d(const char *buf, int w, int h, int upscale, int
if (!buf || w <= 0 || h <= 0)
REN_RET(0, REN_INVAL)
glGenTextures(1, &t);
GL(glGenTextures(1, &t))
if (!t) REN_RET(0, REN_TEXTURE)
glBindTexture(GL_TEXTURE_2D, t);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, w, h, 0, GL_RGB, GL_UNSIGNED_BYTE, buf);
GL(glBindTexture(GL_TEXTURE_2D, t))
GL(glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, w, h, 0, GL_RGB, GL_UNSIGNED_BYTE, buf))
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, downscale);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, upscale);
GL(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT))
GL(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT))
GL(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, downscale))
GL(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, upscale))
return t;
}
@ -228,16 +233,16 @@ static GLuint ren_texturergba_2d(const char *buf, int w, int h, int upscale, int
if (!buf || w <= 0 || h <= 0)
REN_RET(0, REN_INVAL)
glGenTextures(1, &t);
GL(glGenTextures(1, &t))
if (!t) REN_RET(0, REN_TEXTURE)
glBindTexture(GL_TEXTURE_2D, t);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, w, h, 0, GL_RGBA, GL_UNSIGNED_BYTE, buf);
GL(glBindTexture(GL_TEXTURE_2D, t))
GL(glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, w, h, 0, GL_RGBA, GL_UNSIGNED_BYTE, buf))
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, downscale);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, upscale);
GL(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT))
GL(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT))
GL(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, downscale))
GL(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, upscale))
return t;
}
@ -250,16 +255,16 @@ static GLuint ren_texturer_2d(const char *buf, int w, int h, int upscale, int do
if (!buf || w <= 0 || h <= 0)
REN_RET(0, REN_INVAL)
glGenTextures(1, &t);
GL(glGenTextures(1, &t))
if (!t) REN_RET(0, REN_TEXTURE)
glBindTexture(GL_TEXTURE_2D, t);
glTexImage2D(GL_TEXTURE_2D, 0, GL_R, w, h, 0, GL_R, GL_UNSIGNED_BYTE, buf);
GL(glBindTexture(GL_TEXTURE_2D, t))
GL(glTexImage2D(GL_TEXTURE_2D, 0, GL_RED, w, h, 0, GL_RED, GL_UNSIGNED_BYTE, buf))
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, downscale);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, upscale);
GL(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT))
GL(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT))
GL(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, downscale))
GL(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, upscale))
return t;
}
@ -269,14 +274,14 @@ static GLuint ren_texturer_2d(const char *buf, int w, int h, int upscale, int do
// FIXME: update only the newly generated character instead of the whole texture
static int update_font_texture(void)
{
glTexSubImage2D(
GL(glTexSubImage2D(
ren.font_texture,
0, 0, 0,
ren.font->width,
ren.font->height,
GL_R,
GL_UNSIGNED_BYTE,
ren.font->atlas);
ren.font->atlas))
font_dump(ren.font, "./atlas.png");
return 0;
}
@ -292,12 +297,12 @@ int ren_init(SDL_Window *w)
REN_RET(-1, REN_CONTEXT)
// select some features
glEnable(GL_BLEND);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
glDisable(GL_CULL_FACE);
glDisable(GL_DEPTH_TEST);
glEnable(GL_SCISSOR_TEST);
glEnable(GL_TEXTURE_2D);
GL(glEnable(GL_BLEND))
GL(glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA))
GL(glDisable(GL_CULL_FACE))
GL(glDisable(GL_DEPTH_TEST))
GL(glEnable(GL_SCISSOR_TEST))
GL(glEnable(GL_TEXTURE_2D))
GLenum glew_err = glewInit();
if (glew_err != GLEW_OK)
@ -322,69 +327,65 @@ int ren_init(SDL_Window *w)
ren.box_stack = vcstack_init();
// generate the font buffer object
glGenBuffers(1, &ren.font_buffer);
GL(glGenBuffers(1, &ren.font_buffer))
if (!ren.font_buffer) REN_RET(-1, REN_BUFFER)
// create the uniforms
ren.viewsize_loc = glGetUniformLocation(ren.font_prog, "viewsize");
ren.viewsize_loc = GL(glGetUniformLocation(ren.font_prog, "viewsize"))
if (ren.viewsize_loc == -1) REN_RET(-1, REN_UNIFORM)
ren.texturesize_loc = glGetUniformLocation(ren.font_prog, "texturesize");
ren.texturesize_loc = GL(glGetUniformLocation(ren.font_prog, "texturesize"))
if (ren.texturesize_loc == -1) REN_RET(-1, REN_UNIFORM)
int width, height;
SDL_GetWindowSize(w, &width, &height);
ren_update_viewport(width, height);
glClearColor(0.3f, 0.3f, 0.3f, 0.f);
glClear(GL_COLOR_BUFFER_BIT);
GL(glClearColor(0.3f, 0.3f, 0.3f, 0.f))
GL(glClear(GL_COLOR_BUFFER_BIT))
return 0;
}
#define GLERR() {int a = glGetError(); if (a != GL_NO_ERROR) printf("glError: %d %s\n", a, glerr[a]);}
static int ren_draw_font_stack(void)
{
glUseProgram(ren.font_prog);
glBindBuffer(GL_ARRAY_BUFFER, ren.font_buffer);
GL(glUseProgram(ren.font_prog))
GL(glBindBuffer(GL_ARRAY_BUFFER, ren.font_buffer))
glViewport(0, 0, ren.width, ren.height);
glScissor(ren.s_x, ren.s_y, ren.s_w, ren.s_h);
glUniform2i(ren.viewsize_loc, ren.width, ren.height);
glUniform2i(ren.texturesize_loc, ren.font->width, ren.font->height);
GLERR();
GL(glViewport(0, 0, ren.width, ren.height))
GL(glScissor(ren.s_x, ren.s_y, ren.s_w, ren.s_h))
GL(glUniform2i(ren.viewsize_loc, ren.width, ren.height))
GL(glUniform2i(ren.texturesize_loc, ren.font->width, ren.font->height))
glEnableVertexAttribArray(REN_VERTEX_IDX);
glEnableVertexAttribArray(REN_UV_IDX);
GL(glEnableVertexAttribArray(REN_VERTEX_IDX))
GL(glEnableVertexAttribArray(REN_UV_IDX))
// when passing ints to glVertexAttribPointer they are automatically
// converted to floats
glVertexAttribPointer(
GL(glVertexAttribPointer(
REN_VERTEX_IDX,
2,
GL_INT,
GL_FALSE,
sizeof(struct v_text),
0);
GLERR();
glVertexAttribPointer(
0))
GL(glVertexAttribPointer(
REN_UV_IDX,
2,
GL_INT,
GL_FALSE,
sizeof(struct v_text),
(void*)sizeof(vec2_i));
GLERR();
(void*)sizeof(vec2_i)))
// TODO: implement size and damage tracking on stacks
glBufferData(
GL(glBufferData(
GL_ARRAY_BUFFER,
ren.font_stack.idx*sizeof(struct v_text),
ren.font_stack.items,
GL_DYNAMIC_DRAW);
glDrawArrays(GL_TRIANGLES, 0, ren.font_stack.idx);
GLERR();
glDisableVertexAttribArray(REN_VERTEX_IDX);
glDisableVertexAttribArray(REN_UV_IDX);
glBindBuffer(GL_ARRAY_BUFFER, 0);
glUseProgram(0);
GL_DYNAMIC_DRAW))
GL(glDrawArrays(GL_TRIANGLES, 0, ren.font_stack.idx))
GL(glDisableVertexAttribArray(REN_VERTEX_IDX))
GL(glDisableVertexAttribArray(REN_UV_IDX))
GL(glBindBuffer(GL_ARRAY_BUFFER, 0))
GL(glUseProgram(0))
return 0;
}
@ -425,6 +426,7 @@ int ren_render_text(const char *str, int x, int y, int w, int h, int size)
// x1,y1 x2,y2
const struct font_glyph *g;
struct font_glyph c;
size_t ret, off;
uint_least32_t cp;
int updated, gx = x, gy = y;
@ -436,45 +438,45 @@ int ren_render_text(const char *str, int x, int y, int w, int h, int size)
if (update_font_texture())
REN_RET(-1, REN_TEXTURE);
}
printf("g: u=%d v=%d w=%d h=%d a=%d x=%d y=%d\n", g->u, g->v, g->w, g->h, g->a, g->x, g->y);
c = *g;
printf("g: u=%d v=%d w=%d h=%d a=%d x=%d y=%d\n", c.u, c.v, c.w, c.h, c.a, c.x, c.y);
// x1,y1
v = (struct v_text){
.pos = { .x = gx+g->x, .y = gy+g->y+g->h },
.uv = { .u = g->u, .v = g->v+g->h },
.pos = { .x = gx+c.x, .y = gy+c.y+c.h },
.uv = { .u = c.u, .v = c.v+c.h },
};
vtstack_push(&ren.font_stack, &v);
// x2,y2
v = (struct v_text){
.pos = { .x = gx+g->x+g->w, .y = gy+g->y+g->h },
.uv = { .u = g->u+g->w, .v = g->v+g->h },
.pos = { .x = gx+c.x+c.w, .y = gy+c.y+c.h },
.uv = { .u = c.u+c.w, .v = c.v+c.h },
};
vtstack_push(&ren.font_stack, &v);
// x3,y3
v = (struct v_text){
.pos = { .x = gx+g->x+g->w, .y = gy+g->y },
.uv = { .u = g->u+g->w, .v = g->v },
.pos = { .x = gx+c.x+c.w, .y = gy+c.y },
.uv = { .u = c.u+c.w, .v = c.v },
};
vtstack_push(&ren.font_stack, &v);
vtstack_push(&ren.font_stack, &v);
// x4,y4
v = (struct v_text){
.pos = { .x = gx+g->x, .y = gy+g->y },
.uv = { .u = g->u, .v = g->v },
.pos = { .x = gx+c.x, .y = gy+c.y },
.uv = { .u = c.u, .v = c.v },
};
vtstack_push(&ren.font_stack, &v);
// x1,y1
v = (struct v_text){
.pos = { .x = gx+g->x, .y = gy+g->y+g->h },
.uv = { .u = g->u, .v = g->v+g->h },
.pos = { .x = gx+c.x, .y = gy+c.y+c.h },
.uv = { .u = c.u, .v = c.v+c.h },
};
vtstack_push(&ren.font_stack, &v);
// TODO: possible kerning needs to be applied here
// FIXME: advance is too large
//gx += g->w + g->a;
gx += g->w + g->x + 1;
//gx += c.w + c.a;
gx += c.w + c.x + 1;
if (cp == '\n')
gy += ren.font->glyph_max_h;
// TODO: encode and/or store line height
@ -492,10 +494,10 @@ int ren_render_text(const char *str, int x, int y, int w, int h, int size)
int ren_free(void)
{
glUseProgram(0);
glBindBuffer(GL_ARRAY_BUFFER, 0);
glDeleteTextures(1, &ren.font_texture);
glDeleteBuffers(1, &ren.font_buffer);
GL(glUseProgram(0))
GL(glBindBuffer(GL_ARRAY_BUFFER, 0))
GL(glDeleteTextures(1, &ren.font_texture))
GL(glDeleteBuffers(1, &ren.font_buffer))
SDL_GL_DeleteContext(ren.gl);
vtstack_free(&ren.font_stack);
vcstack_free(&ren.box_stack);

Binary file not shown.

@ -4,6 +4,7 @@
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <err.h>
@ -85,7 +86,8 @@ void dump_file(const char *path, char **buf, int *buf_len)
rewind(fp);
if (*buf_len == (off_t)-1)
err(EXIT_FAILURE, "lseek() failed");
*buf = emalloc(*buf_len);
*buf = emalloc(*buf_len+1);
memset(*buf, 0, *buf_len+1);
int ret = fread(*buf, 1, *buf_len, fp);
if (ret != *buf_len)
err(EXIT_FAILURE, "fread() returned short %s", ferror(fp) ? "stream error" : feof(fp) ? "EOF reached" : "unknown error");

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