nuclear@2: #include <stdio.h>
nuclear@2: #include <stdlib.h>
nuclear@2: #include <string.h>
nuclear@2: #include <assert.h>
nuclear@2: #include <windows.h>
nuclear@2: #include <GL/gl.h>
nuclear@2: #include "glext.h"
nuclear@2: #include "wglext.h"
nuclear@2: #include "app.h"
nuclear@2: 
nuclear@2: static void draw_screen(long time_msec);
nuclear@2: static unsigned int create_program(const char *vsdr, const char *psdr);
nuclear@2: static unsigned int create_shader(unsigned int type, const char *sdr);
nuclear@2: static unsigned int next_pow2(unsigned int x);
nuclear@2: static int enable_vsync(void);
nuclear@2: static int init_glext(void);
nuclear@2: static void calc_image_proj(float img_aspect, float *xform);
nuclear@2: 
nuclear@2: extern int scr_width, scr_height;
nuclear@2: 
nuclear@2: PFNWGLSWAPINTERVALEXTPROC wgl_swap_interval;
nuclear@2: 
nuclear@2: /* multitexture */
nuclear@2: PFNGLACTIVETEXTUREPROC gl_active_texture;
nuclear@2: 
nuclear@2: /* shader API entry points */
nuclear@2: PFNGLCREATEPROGRAMPROC gl_create_program;
nuclear@2: PFNGLDELETEPROGRAMPROC gl_delete_program;
nuclear@2: PFNGLCREATESHADERPROC gl_create_shader;
nuclear@2: PFNGLDELETESHADERPROC gl_delete_shader;
nuclear@2: PFNGLSHADERSOURCEPROC gl_shader_source;
nuclear@2: PFNGLCOMPILESHADERPROC gl_compile_shader;
nuclear@2: PFNGLGETSHADERIVPROC gl_get_shaderiv;
nuclear@2: PFNGLGETSHADERINFOLOGPROC gl_get_shader_info_log;
nuclear@2: PFNGLATTACHSHADERPROC gl_attach_shader;
nuclear@2: PFNGLLINKPROGRAMPROC gl_link_program;
nuclear@2: PFNGLGETPROGRAMIVPROC gl_get_programiv;
nuclear@2: PFNGLGETPROGRAMINFOLOGPROC gl_get_program_info_log;
nuclear@2: PFNGLUSEPROGRAMPROC gl_use_program;
nuclear@2: PFNGLGETUNIFORMLOCATIONPROC gl_get_uniform_location;
nuclear@2: PFNGLUNIFORM1IPROC gl_uniform1i;
nuclear@2: PFNGLUNIFORM2FPROC gl_uniform2f;
nuclear@2: PFNGLUNIFORMMATRIX4FVPROC gl_uniform_matrix4fv;
nuclear@2: 
nuclear@2: enum { FIT_FULL, FIT_CROP, FIT_STRETCH };
nuclear@2: static int fit_mode = FIT_FULL;
nuclear@2: static float crop_zoom = 1.0f;
nuclear@2: static float crop_dir[] = {0.0f, 0.0f};
nuclear@2: 
nuclear@2: static int tex_xsz, tex_ysz;
nuclear@2: static unsigned int img_tex, pal_tex, prog;
nuclear@2: static unsigned char pal[256 * 3];
nuclear@2: static int pal_valid;
nuclear@2: 
nuclear@2: static const char *vsdr =
nuclear@2: 	"uniform mat4 xform;\n"
nuclear@2: 	"uniform vec2 uvscale;\n"
nuclear@2: 	"varying vec2 uv;\n"
nuclear@2: 	"void main()\n"
nuclear@2: 	"{\n"
nuclear@2: 	"\tgl_Position = xform * gl_Vertex;\n"
nuclear@2: 	"\tuv = (gl_Vertex.xy * vec2(0.5, -0.5) + 0.5) * uvscale;\n"
nuclear@2: 	"}\n";
nuclear@2: 
nuclear@2: static const char *psdr =
nuclear@2: 	"uniform sampler2D img_tex;\n"
nuclear@2: 	"uniform sampler1D pal_tex;\n"
nuclear@2: 	"varying vec2 uv;\n"
nuclear@2: 	"void main()\n"
nuclear@2: 	"{\n"
nuclear@2: 	"\tfloat cidx = texture2D(img_tex, uv).x;\n"
nuclear@2: 	"\tvec3 color = texture1D(pal_tex, cidx).xyz;\n"
nuclear@2: 	"\tgl_FragColor.xyz = color;\n"
nuclear@2: 	"\tgl_FragColor.a = 1.0;\n"
nuclear@2: 	"}\n";
nuclear@2: 
nuclear@2: static int xform_loc, uvscale_loc;
nuclear@2: 
nuclear@2: void resize(int xsz, int ysz)
nuclear@2: {
nuclear@2: 	if(xsz == fbwidth && ysz == fbheight) return;
nuclear@2: 
nuclear@2: 	fbwidth = xsz;
nuclear@2: 	fbheight = ysz;
nuclear@2: 
nuclear@2: 	tex_xsz = next_pow2(fbwidth);
nuclear@2: 	tex_ysz = next_pow2(fbheight);
nuclear@2: 
nuclear@2: 	glBindTexture(GL_TEXTURE_2D, img_tex);
nuclear@2: 	glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE, tex_xsz, tex_ysz, 0, GL_LUMINANCE, GL_UNSIGNED_BYTE, 0);
nuclear@2: }
nuclear@2: 
nuclear@2: 
nuclear@2: void set_palette(int idx, int r, int g, int b)
nuclear@2: {
nuclear@2: 	unsigned char *pptr = pal + idx * 3;
nuclear@2: 	pptr[0] = r;
nuclear@2: 	pptr[1] = g;
nuclear@2: 	pptr[2] = b;
nuclear@2: 	pal_valid = 0;
nuclear@2: }
nuclear@2: 
nuclear@2: void colcycle_init(void)
nuclear@2: {
nuclear@2: 	int loc;
nuclear@2: 	char *argv[] = {"colcycle", "foo.lbm", 0};
nuclear@2: 
nuclear@2: 	init_glext();
nuclear@2: 
nuclear@2: 	fbwidth = 640;
nuclear@2: 	fbheight = 480;
nuclear@2: 	fbpixels = malloc(fbwidth * fbheight);
nuclear@2: 
nuclear@2: 	colc_init(2, argv);
nuclear@2: 
nuclear@2: 	tex_xsz = next_pow2(fbwidth);
nuclear@2: 	tex_ysz = next_pow2(fbheight);
nuclear@2: 
nuclear@2: 	glGenTextures(1, &img_tex);
nuclear@2: 	glBindTexture(GL_TEXTURE_2D, img_tex);
nuclear@2: 	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
nuclear@2: 	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
nuclear@2: 	glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE, tex_xsz, tex_ysz, 0, GL_LUMINANCE, GL_UNSIGNED_BYTE, 0);
nuclear@2: 	glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, fbwidth, fbheight, GL_LUMINANCE, GL_UNSIGNED_BYTE, fbpixels);
nuclear@2: 
nuclear@2: 	glGenTextures(1, &pal_tex);
nuclear@2: 	glBindTexture(GL_TEXTURE_1D, pal_tex);
nuclear@2: 	glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
nuclear@2: 	glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
nuclear@2: 	glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
nuclear@2: 	glTexImage1D(GL_TEXTURE_1D, 0, GL_RGB, 256, 0, GL_RGB, GL_UNSIGNED_BYTE, pal);
nuclear@2: 
nuclear@2: 	if((prog = create_program(vsdr, psdr))) {
nuclear@2: 		gl_use_program(prog);
nuclear@2: 		if((loc = gl_get_uniform_location(prog, "img_tex")) >= 0) {
nuclear@2: 			gl_uniform1i(loc, 0);
nuclear@2: 		}
nuclear@2: 		if((loc = gl_get_uniform_location(prog, "pal_tex")) >= 0) {
nuclear@2: 			gl_uniform1i(loc, 1);
nuclear@2: 		}
nuclear@2: 		if((uvscale_loc = gl_get_uniform_location(prog, "uvscale")) >= 0) {
nuclear@2: 			gl_uniform2f(uvscale_loc, (float)fbwidth / (float)tex_xsz, (float)fbheight / (float)tex_ysz);
nuclear@2: 		}
nuclear@2: 		xform_loc = gl_get_uniform_location(prog, "xform");
nuclear@2: 	}
nuclear@2: 	gl_use_program(0);
nuclear@2: 
nuclear@2: 	if(enable_vsync() == -1) {
nuclear@2: 		fprintf(stderr, "failed to enable vsync\n");
nuclear@2: 	}
nuclear@2: }
nuclear@2: 
nuclear@2: void colcycle_cleanup(void)
nuclear@2: {
nuclear@2: 	colc_cleanup();
nuclear@2: }
nuclear@2: 
nuclear@2: void colcycle_draw(long time_msec)
nuclear@2: {
nuclear@2: 	float xform[16];
nuclear@2: 
nuclear@2: 	glClearColor(0, 0, 0, 1);
nuclear@2: 	glClear(GL_COLOR_BUFFER_BIT);
nuclear@2: 
nuclear@2: 	glViewport(0, 0, scr_width, scr_height);
nuclear@2: 
nuclear@2: 	calc_image_proj((float)fbwidth / (float)fbheight, xform);
nuclear@2: 
nuclear@2: 	gl_use_program(prog);
nuclear@2: 	if(xform_loc >= 0) {
nuclear@2: 		gl_uniform_matrix4fv(xform_loc, 1, GL_FALSE, xform);
nuclear@2: 	}
nuclear@2: 
nuclear@2: 	draw_screen(time_msec);
nuclear@2: }
nuclear@2: 
nuclear@2: static void draw_screen(long time_msec)
nuclear@2: {
nuclear@2: 	*(uint32_t*)fbpixels = 0xbadf00d;
nuclear@2: 	colc_draw(time_msec);
nuclear@2: 
nuclear@2: 	if(*(uint32_t*)fbpixels != 0xbadf00d) {
nuclear@2: 		/* update texture data if the framebuffer changed */
nuclear@2: 		glBindTexture(GL_TEXTURE_2D, img_tex);
nuclear@2: 		glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, fbwidth, fbheight, GL_LUMINANCE, GL_UNSIGNED_BYTE, fbpixels);
nuclear@2: 	}
nuclear@2: 	if(!pal_valid) {
nuclear@2: 		/* update the palette texture */
nuclear@2: 		glBindTexture(GL_TEXTURE_1D, pal_tex);
nuclear@2: 		glTexSubImage1D(GL_TEXTURE_1D, 0, 0, 256, GL_RGB, GL_UNSIGNED_BYTE, pal);
nuclear@2: 		pal_valid = 1;
nuclear@2: 	}
nuclear@2: 
nuclear@2: 	gl_active_texture(GL_TEXTURE0);
nuclear@2: 	glBindTexture(GL_TEXTURE_2D, img_tex);
nuclear@2: 	gl_active_texture(GL_TEXTURE1);
nuclear@2: 	glBindTexture(GL_TEXTURE_1D, pal_tex);
nuclear@2: 	gl_active_texture(GL_TEXTURE0);
nuclear@2: 
nuclear@2: 	glBegin(GL_QUADS);
nuclear@2: 	glVertex2f(-1, -1);
nuclear@2: 	glVertex2f(1, -1);
nuclear@2: 	glVertex2f(1, 1);
nuclear@2: 	glVertex2f(-1, 1);
nuclear@2: 	glEnd();
nuclear@2: 
nuclear@2: 	assert(glGetError() == GL_NO_ERROR);
nuclear@2: }
nuclear@2: 
nuclear@2: static unsigned int create_program(const char *vsdr, const char *psdr)
nuclear@2: {
nuclear@2: 	unsigned int vs, ps, prog;
nuclear@2: 	int status, info_len;
nuclear@2: 
nuclear@2: 	if(!(vs = create_shader(GL_VERTEX_SHADER, vsdr))) {
nuclear@2: 		return 0;
nuclear@2: 	}
nuclear@2: 	if(!(ps = create_shader(GL_FRAGMENT_SHADER, psdr))) {
nuclear@2: 		gl_delete_shader(vs);
nuclear@2: 		return 0;
nuclear@2: 	}
nuclear@2: 
nuclear@2: 	prog = gl_create_program();
nuclear@2: 	gl_attach_shader(prog, vs);
nuclear@2: 	gl_attach_shader(prog, ps);
nuclear@2: 	gl_link_program(prog);
nuclear@2: 
nuclear@2: 	gl_get_programiv(prog, GL_LINK_STATUS, &status);
nuclear@2: 	if(!status) {
nuclear@2: 		fprintf(stderr, "failed to link shader program\n");
nuclear@2: 		gl_delete_program(prog);
nuclear@2: 		prog = 0;
nuclear@2: 	}
nuclear@2: 
nuclear@2: 	gl_get_programiv(prog, GL_INFO_LOG_LENGTH, &info_len);
nuclear@2: 	if(info_len) {
nuclear@2: 		char *buf = alloca(info_len + 1);
nuclear@2: 		gl_get_program_info_log(prog, info_len, 0, buf);
nuclear@2: 		buf[info_len] = 0;
nuclear@2: 		if(buf[0]) {
nuclear@2: 			fprintf(stderr, "linker output:\n%s\n", buf);
nuclear@2: 		}
nuclear@2: 	}
nuclear@2: 
nuclear@2: 	if(!status) {
nuclear@2: 		gl_delete_program(prog);
nuclear@2: 		prog = 0;
nuclear@2: 	}
nuclear@2: 	return prog;
nuclear@2: }
nuclear@2: 
nuclear@2: static unsigned int create_shader(unsigned int type, const char *src)
nuclear@2: {
nuclear@2: 	unsigned int sdr;
nuclear@2: 	int status, info_len;
nuclear@2: 
nuclear@2: 	sdr = gl_create_shader(type);
nuclear@2: 	gl_shader_source(sdr, 1, &src, 0);
nuclear@2: 	gl_compile_shader(sdr);
nuclear@2: 
nuclear@2: 	gl_get_shaderiv(sdr, GL_COMPILE_STATUS, &status);
nuclear@2: 	if(!status) {
nuclear@2: 		fprintf(stderr, "failed to compile %s shader\n", type == GL_VERTEX_SHADER ? "vertex" : "pixel");
nuclear@2: 	}
nuclear@2: 
nuclear@2: 	gl_get_shaderiv(sdr, GL_INFO_LOG_LENGTH, &info_len);
nuclear@2: 	if(info_len) {
nuclear@2: 		char *buf = alloca(info_len + 1);
nuclear@2: 		gl_get_shader_info_log(sdr, info_len, 0, buf);
nuclear@2: 		buf[info_len] = 0;
nuclear@2: 		if(buf[0]) {
nuclear@2: 			fprintf(stderr, "compiler output:\n%s\n", buf);
nuclear@2: 		}
nuclear@2: 	}
nuclear@2: 
nuclear@2: 	if(!status) {
nuclear@2: 		gl_delete_shader(sdr);
nuclear@2: 		sdr = 0;
nuclear@2: 	}
nuclear@2: 	return sdr;
nuclear@2: }
nuclear@2: 
nuclear@2: static unsigned int next_pow2(unsigned int x)
nuclear@2: {
nuclear@2: 	--x;
nuclear@2: 	x |= x >> 1;
nuclear@2: 	x |= x >> 2;
nuclear@2: 	x |= x >> 4;
nuclear@2: 	x |= x >> 8;
nuclear@2: 	x |= x >> 16;
nuclear@2: 	return x + 1;
nuclear@2: }
nuclear@2: 
nuclear@2: static int enable_vsync(void)
nuclear@2: {
nuclear@2: 	if(wgl_swap_interval) {
nuclear@2: 		wgl_swap_interval(1);
nuclear@2: 	}
nuclear@2: 	return -1;
nuclear@2: }
nuclear@2: 
nuclear@2: static int init_glext(void)
nuclear@2: {
nuclear@2: 	static int init_done;
nuclear@2: 	const char *extstr;
nuclear@2: 	PFNWGLGETEXTENSIONSSTRINGEXTPROC wgl_get_extstr_ext;
nuclear@2: 
nuclear@2: 	if(init_done) return 0;
nuclear@2: 	init_done = 1;
nuclear@2: 
nuclear@2: 	/* WGL extensions */
nuclear@2: 	if((wgl_get_extstr_ext = (PFNWGLGETEXTENSIONSSTRINGEXTPROC)wglGetProcAddress("wglGetExtensionsStringEXT"))) {
nuclear@2: 		if(!(extstr = wgl_get_extstr_ext())) {
nuclear@2: 			fprintf(stderr, "failed to retrieve WGL extensions string\n");
nuclear@2: 			return -1;
nuclear@2: 		}
nuclear@2: 	} else {
nuclear@2: 		fprintf(stderr, "wglGetExtensionsString not found\n");
nuclear@2: 		return -1;
nuclear@2: 	}
nuclear@2: 	if(strstr(extstr, "WGL_EXT_swap_control")) {
nuclear@2: 		wgl_swap_interval = (PFNWGLSWAPINTERVALEXTPROC)wglGetProcAddress("wglSwapIntervalEXT");
nuclear@2: 	}
nuclear@2: 
nuclear@2: 	/* OpenGL extensions */
nuclear@2: 	if(!(extstr = (const char*)glGetString(GL_EXTENSIONS))) {
nuclear@2: 		fprintf(stderr, "failed to retrieve GL extensions string\n");
nuclear@2: 		return -1;
nuclear@2: 	}
nuclear@2: 	/* proceed to ignore the extensions string and just attempt to load entry points,
nuclear@2: 	 * because we want to use the GL2.0 style of the API, instead of the clunkier ARB one
nuclear@2: 	 */
nuclear@2: 	if(!(gl_create_program = (PFNGLCREATEPROGRAMPROC)wglGetProcAddress("glCreateProgram"))) {
nuclear@2: 		fprintf(stderr, "failed to find the OpenGL shader API entry points\n");
nuclear@2: 		return -1;
nuclear@2: 	}
nuclear@2: 	/* assume everything else is there if glCreateProgram is there */
nuclear@2: 	gl_delete_program = (PFNGLDELETEPROGRAMPROC)wglGetProcAddress("glDeleteProgram");
nuclear@2: 	gl_create_shader = (PFNGLCREATESHADERPROC)wglGetProcAddress("glCreateShader");
nuclear@2: 	gl_delete_shader = (PFNGLDELETESHADERPROC)wglGetProcAddress("glDeleteShader");
nuclear@2: 	gl_shader_source = (PFNGLSHADERSOURCEPROC)wglGetProcAddress("glShaderSource");
nuclear@2: 	gl_compile_shader = (PFNGLCOMPILESHADERPROC)wglGetProcAddress("glCompileShader");
nuclear@2: 	gl_get_shaderiv = (PFNGLGETSHADERIVPROC)wglGetProcAddress("glGetShaderiv");
nuclear@2: 	gl_get_shader_info_log = (PFNGLGETSHADERINFOLOGPROC)wglGetProcAddress("glGetShaderInfoLog");
nuclear@2: 	gl_attach_shader = (PFNGLATTACHSHADERPROC)wglGetProcAddress("glAttachShader");
nuclear@2: 	gl_link_program = (PFNGLLINKPROGRAMPROC)wglGetProcAddress("glLinkProgram");
nuclear@2: 	gl_get_programiv = (PFNGLGETPROGRAMIVPROC)wglGetProcAddress("glGetProgramiv");
nuclear@2: 	gl_get_program_info_log = (PFNGLGETPROGRAMINFOLOGPROC)wglGetProcAddress("glGetProgramInfoLog");
nuclear@2: 	gl_use_program = (PFNGLUSEPROGRAMPROC)wglGetProcAddress("glUseProgram");
nuclear@2: 	gl_get_uniform_location = (PFNGLGETUNIFORMLOCATIONPROC)wglGetProcAddress("glGetUniformLocation");
nuclear@2: 	gl_uniform1i = (PFNGLUNIFORM1IPROC)wglGetProcAddress("glUniform1i");
nuclear@2: 	gl_uniform2f = (PFNGLUNIFORM2FPROC)wglGetProcAddress("glUniform2f");
nuclear@2: 	gl_uniform_matrix4fv = (PFNGLUNIFORMMATRIX4FVPROC)wglGetProcAddress("glUniformMatrix4fv");
nuclear@2: 
nuclear@2: 	if(!(gl_active_texture = (PFNGLACTIVETEXTUREPROC)wglGetProcAddress("glActiveTexture"))) {
nuclear@2: 		fprintf(stderr, "failed to find the multitexturing entry points\n");
nuclear@2: 		return -1;
nuclear@2: 	}
nuclear@2: 
nuclear@2: 	return 0;
nuclear@2: }
nuclear@2: 
nuclear@2: static void calc_image_proj(float img_aspect, float *xform)
nuclear@2: {
nuclear@2: 	static const float ident[] = {1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1};
nuclear@2: 	float vpscale;
nuclear@2: 	float aspect = (float)scr_width / (float)scr_height;
nuclear@2: 
nuclear@2: 	memcpy(xform, ident, sizeof ident);
nuclear@2: 
nuclear@2: 	if(fit_mode != FIT_STRETCH) {
nuclear@2: 		if(aspect > img_aspect) {
nuclear@2: 			vpscale = xform[0] = img_aspect / aspect;
nuclear@2: 			xform[5] = 1.0f;
nuclear@2: 		} else {
nuclear@2: 			vpscale = xform[5] = aspect / img_aspect;
nuclear@2: 			xform[0] = 1.0f;
nuclear@2: 		}
nuclear@2: 
nuclear@2: 		if(fit_mode == FIT_CROP) {
nuclear@2: 			float cropscale, maxpan, tx, ty;
nuclear@2: 
nuclear@2: 			cropscale = 1.0f / vpscale;
nuclear@2: 			cropscale = 1.0f + (cropscale - 1.0f) * crop_zoom;
nuclear@2: 			maxpan = cropscale - 1.0f;
nuclear@2: 
nuclear@2: 			xform[0] *= cropscale;
nuclear@2: 			xform[5] *= cropscale;
nuclear@2: 
nuclear@2: 			if(aspect > img_aspect) {
nuclear@2: 				tx = 0.0f;
nuclear@2: 				ty = -crop_dir[1] * maxpan;
nuclear@2: 			} else {
nuclear@2: 				tx = -crop_dir[0] * maxpan;
nuclear@2: 				ty = 0.0f;
nuclear@2: 			}
nuclear@2: 
nuclear@2: 			xform[12] = tx;
nuclear@2: 			xform[13] = ty;
nuclear@2: 		} else {
nuclear@2: 			xform[12] = xform[13] = 0.0f;
nuclear@2: 		}
nuclear@2: 	}
nuclear@2: }
nuclear@2: