added framebuffer; also opengl debugging

include/framebuffer.h

@@ -0,0 +1,20 @@
+#ifndef GUARD_4770FE04EA612B028DF68960A453BD0B
+#define GUARD_4770FE04EA612B028DF68960A453BD0B
+
+#include "types.h"
+#include "vec2i.h"
+
+struct sw_framebuffer {
+	struct sw_vec2i size;
+	u32 _fb, _fbtex, _fbdepth;
+};
+
+struct sw_framebuffer *sw_framebuffer_create(struct sw_vec2i size);
+void sw_framebuffer_destroy(struct sw_framebuffer *fb);
+
+void sw_framebuffer_static_init();
+
+void sw_framebuffer_copy_to_screen(struct sw_framebuffer *fb);
+void sw_framebuffer_resize(struct sw_framebuffer *fb, struct sw_vec2i new_size);
+
+#endif /* GUARD_4770FE04EA612B028DF68960A453BD0B */

include/scaler.h

@@ -0,0 +1,8 @@
+#ifndef GUARD_D3B2B8EAB7F3D9A513B3C06FAAF6357E
+#define GUARD_D3B2B8EAB7F3D9A513B3C06FAAF6357E
+
+#define SW_SCALE_STRETCH 0
+#define SW_SCALE_ASPECT 1
+#define SW_SCALE_INTEGER 2
+
+#endif /* GUARD_D3B2B8EAB7F3D9A513B3C06FAAF6357E */

include/window.h

@@ -1,14 +1,19 @@
 #ifndef GUARD_F247452E0BF1EC9CD9131C2A6FD281CA
 #define GUARD_F247452E0BF1EC9CD9131C2A6FD281CA
 
+#include "framebuffer.h"
+#include "types.h"
 #include "vec2i.h"
 
 struct GLFWwindow;
 
 struct sw_window {
 	struct sw_vec2i size;
+	struct sw_vec2i real_size;
+	i32 scaler;
 
 	struct GLFWwindow *_window;
+	struct sw_framebuffer *_scaler_fb;
 };
 
 struct sw_window *sw_window_create(struct sw_vec2i size, char *title);

meson.build

@@ -43,6 +43,7 @@ skunk_sources = [
 	'src/color32.c',
 	'src/error.c',
 	'src/file.c',
+	'src/framebuffer.c',
 	'src/gsa.c',
 	'src/image32.c',
 	'src/image8.c',

src/framebuffer.c

@@ -0,0 +1,134 @@
+#include "framebuffer.h"
+#include "error.h"
+#include "gl.h"
+#include "shader.h"
+#include <stdlib.h>
+
+static struct sw_shaderprogram program_copy;
+
+static char *vert_copy = "#version 300 es\n\
+precision highp float;\
+in vec2 pos;\
+out vec2 out_tex_coord;\
+void main() {\
+	gl_Position = vec4(pos, 0.0f, 1.0f);\
+	out_tex_coord = vec2(pos.x * 0.5 + 0.5, pos.y * 0.5 + 0.5);\
+}";
+
+static char *frag_copy = "#version 300 es\n\
+precision highp float;\
+in vec2 out_tex_coord;\
+uniform sampler2D tex;\
+out vec4 color;\
+void main() {\
+	vec4 col = texture(tex, out_tex_coord);\
+if(col.a > 0.0) {\
+	color = col;\
+}\
+}";
+
+static f32 screen_rect[12] = {
+    -1.f, -1.f, 1.f, -1.f, -1.f, 1.f, 1.f, -1.f, -1.f, 1.f, 1.f, 1.f};
+static u32 vao, vbo;
+
+struct sw_framebuffer *sw_framebuffer_create(struct sw_vec2i size) {
+	struct sw_framebuffer *fb;
+
+	sw_log("init framebuffer");
+	fb = malloc(sizeof(struct sw_framebuffer));
+	glGenFramebuffers(1, &fb->_fb);
+	glGenTextures(1, &fb->_fbtex);
+	glGenTextures(1, &fb->_fbdepth);
+	sw_framebuffer_resize(fb, size);
+
+	return fb;
+}
+
+void sw_framebuffer_destroy(struct sw_framebuffer *fb) {
+	glDeleteTextures(1, &fb->_fbtex);
+	glDeleteFramebuffers(1, &fb->_fb);
+}
+
+void sw_framebuffer_static_init() {
+	sw_log("init static framebuffer");
+
+	program_copy = sw_shaderprogram_create(vert_copy, frag_copy);
+
+	sw_log("init static framebuffer vao");
+	glGenVertexArrays(1, &vao);
+	glBindVertexArray(vao);
+
+	sw_log("init static framebuffer vbo");
+	glGenBuffers(1, &vbo);
+	glBindBuffer(GL_ARRAY_BUFFER, vbo);
+	glBufferData(
+	    GL_ARRAY_BUFFER, sizeof(f32) * 12, screen_rect, GL_STATIC_DRAW
+	);
+	glGetAttribLocation(program_copy._program, "pos");
+	glVertexAttribPointer(
+	    glGetAttribLocation(program_copy._program, "pos"),
+	    2,
+	    GL_FLOAT,
+	    GL_FALSE,
+	    0,
+	    0
+	);
+
+	glEnableVertexAttribArray(glGetAttribLocation(program_copy._program, "pos")
+	);
+
+	glBindVertexArray(0);
+	sw_log("init static framebuffer done");
+}
+
+void sw_framebuffer_copy_to_screen(struct sw_framebuffer *fb) {
+	glBindVertexArray(vao);
+	sw_shaderprogram_use(program_copy);
+	glBindTexture(GL_TEXTURE_2D, fb->_fbtex);
+	glBindFramebuffer(GL_FRAMEBUFFER, 0);
+
+	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+
+	glDrawArrays(GL_TRIANGLES, 0, 12);
+	glBindVertexArray(0);
+}
+
+void sw_framebuffer_resize(
+    struct sw_framebuffer *fb, struct sw_vec2i new_size
+) {
+	sw_log("resize framebuffer to %ix%i", new_size.x, new_size.y);
+	fb->size = new_size;
+	glBindFramebuffer(GL_FRAMEBUFFER, fb->_fb);
+	glBindTexture(GL_TEXTURE_2D, fb->_fbtex);
+	glTexImage2D(
+	    GL_TEXTURE_2D,
+	    0,
+	    GL_RGBA8,
+	    new_size.x,
+	    new_size.y,
+	    0,
+	    GL_RGBA,
+	    GL_UNSIGNED_BYTE,
+	    0
+	);
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+	glFramebufferTexture(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, fb->_fbtex, 0);
+
+	glBindTexture(GL_TEXTURE_2D, fb->_fbdepth);
+	glTexImage2D(
+	    GL_TEXTURE_2D,
+	    0,
+	    GL_DEPTH_COMPONENT,
+	    new_size.x,
+	    new_size.y,
+	    0,
+	    GL_DEPTH_COMPONENT,
+	    GL_UNSIGNED_SHORT,
+	    0
+	);
+
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+	glFramebufferTexture(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, fb->_fbdepth, 0);
+}

src/gsa.c

@@ -54,18 +54,17 @@ static i32 next_render_vert;
 static struct render_vert render_verts[MAX_RENDER_VERTS * 4];
 static sw_color32 palette[256];
 static f32 palette_gl[1024];
+static u32 tex;
 
 int gsa_main(int argc, char *argv[]) {
 	(void)argc;
 	(void)argv;
-	u32 tex;
 	i32 max_components;
 
 	sw_log("Initialising GameSkunkAdvance v0.0");
 
 	_win = sw_window_create(sw_vec2i(304, 176), "Game Skunk Advance v0.0");
 	program = sw_shaderprogram_create(vert_source, frag_source);
-	sw_shaderprogram_use(program);
 
 	glGetIntegerv(GL_MAX_VERTEX_UNIFORM_COMPONENTS, &max_components);
 	sw_log("GL_MAX_VERTEX_UNIFORM_COMPONENTS: %i", max_components);
@@ -88,9 +87,11 @@ int gsa_main(int argc, char *argv[]) {
 	    _gfx->_data
 	);
 
-	glGenBuffers(1, &vao);
+	sw_log("setup gsa vao");
+	glGenVertexArrays(1, &vao);
 	glBindVertexArray(vao);
 
+	sw_log("setup gsa vbo");
 	glGenBuffers(1, &vbo);
 	glBindBuffer(GL_ARRAY_BUFFER, vbo);
 	glVertexAttribPointer(
@@ -112,7 +113,9 @@ int gsa_main(int argc, char *argv[]) {
 	glEnableVertexAttribArray(glGetAttribLocation(program._program, "pos"));
 	glEnableVertexAttribArray(glGetAttribLocation(program._program, "tex_coord")
 	);
+	glBindVertexArray(0);
 
+	sw_log("gsa setup done");
 	init();
 	sw_window_run(_win, _gsa_tick);
 
@@ -202,8 +205,11 @@ void _gsa_tick() {
 	    sw_color32_get_bf(palette[0]),
 	    sw_color32_get_af(palette[0])
 	);
-
+	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 	glBindVertexArray(vao);
+	sw_shaderprogram_use(program);
+	glBindTexture(GL_TEXTURE_2D, tex);
+
 	/* TODO: only do when palette changed */
 	update_palette_gl();
 	glUniform4fv(
@@ -216,5 +222,6 @@ void _gsa_tick() {
 	    GL_DYNAMIC_DRAW
 	);
 	glDrawArrays(GL_TRIANGLES, 0, next_render_vert);
+	glBindVertexArray(0);
 	/* glEnd(); */
 }

src/shader.c

@@ -11,6 +11,8 @@ struct sw_shader sw_shader_create(char const *source, i32 type) {
 	i32 length;
 	i32 ret;
 
+	sw_log("create shader");
+
 	switch(type) {
 	case SW_SHADER_VERTEX:
 		gltype = GL_VERTEX_SHADER;
@@ -44,14 +46,24 @@ struct sw_shaderprogram
 sw_shaderprogram_create(char const *vertex, char const *fragment) {
 	struct sw_shaderprogram program;
 	struct sw_shader v, f;
+	i32 ret;
 
+	sw_log("create shader program");
 	v = sw_shader_create(vertex, SW_SHADER_VERTEX);
 	f = sw_shader_create(fragment, SW_SHADER_FRAGMENT);
 	program._program = glCreateProgram();
 	glAttachShader(program._program, v._shader);
 	glAttachShader(program._program, f._shader);
+	sw_log("link shader");
 	glLinkProgram(program._program);
+	glGetProgramiv(program._program, GL_LINK_STATUS, &ret);
+	if(!ret) {
+		char str[256];
+		i32 len;
 
+		glGetProgramInfoLog(program._program, 256, &len, str);
+		sw_error("Shader Link Error: %s", str);
+	}
 	return program;
 }
 

src/window.c

@@ -2,11 +2,22 @@
 
 #include <stdlib.h>
 
+#include "error.h"
+#include "framebuffer.h"
 #include "gl.h"
 
-void _tick();
-struct sw_window *_tick_window;
-void (*_tick_fn)();
+static void _tick();
+static struct sw_window *_tick_window;
+static void (*_tick_fn)();
+static void GLAPIENTRY gldebug(
+    GLenum source,
+    GLenum type,
+    GLuint id,
+    GLenum severity,
+    GLsizei length,
+    const char *msg,
+    const void *user
+);
 
 struct sw_window *sw_window_create(struct sw_vec2i size, char *title) {
 	struct sw_window *win;
@@ -14,6 +25,7 @@ struct sw_window *sw_window_create(struct sw_vec2i size, char *title) {
 	win = malloc(sizeof(struct sw_window));
 	win->size = size;
 
+	sw_log("init glfw");
 	glfwInit();
 	glfwDefaultWindowHints();
 
@@ -21,16 +33,24 @@ struct sw_window *sw_window_create(struct sw_vec2i size, char *title) {
 	glfwShowWindow(win->_window);
 	glfwMakeContextCurrent(win->_window);
 	glewInit();
+	glEnable(GL_DEBUG_OUTPUT);
+	glDebugMessageCallback(gldebug, 0);
 	glfwSwapInterval(1);
+	sw_log("setup ogl defaults");
 	glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 	glEnable(GL_BLEND);
 	glEnable(GL_DEPTH_TEST);
 
+	sw_framebuffer_static_init(); /* TODO: move elsewhere */
+	win->_scaler_fb = sw_framebuffer_create(size);
+
 	glClearColor(0.1f, 0.2f, 0.3f, 1.f);
+	sw_log("window setup complete");
 	return win;
 }
 
 void sw_window_run(struct sw_window *window, void (*callback)()) {
+	sw_log("run window");
 	_tick_window = window;
 	_tick_fn = callback;
 #ifdef __EMSCRIPTEN__
@@ -45,8 +65,33 @@ void sw_window_run(struct sw_window *window, void (*callback)()) {
 /* private functions */
 
 void _tick() {
-	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+	glBindFramebuffer(GL_FRAMEBUFFER, 0);
+	glBindFramebuffer(GL_FRAMEBUFFER, _tick_window->_scaler_fb->_fb);
 	_tick_fn();
+	glBindFramebuffer(GL_FRAMEBUFFER, 0);
+	sw_framebuffer_copy_to_screen(_tick_window->_scaler_fb);
 	glfwSwapBuffers(_tick_window->_window);
 	glfwPollEvents();
 }
+
+void GLAPIENTRY gldebug(
+    GLenum source,
+    GLenum type,
+    GLuint id,
+    GLenum severity,
+    GLsizei length,
+    const char *msg,
+    const void *user
+) {
+	(void)source;
+	(void)id;
+	(void)severity;
+	(void)length;
+	(void)user;
+
+	if(type == GL_DEBUG_TYPE_ERROR) {
+		sw_error("%s", msg);
+	} else {
+		sw_log("%s", msg);
+	}
+}