# HG changeset patch
# User Mike Pavone <pavone@retrodev.com>
# Date 1383098959 25200
# Node ID 251fe7a75a14ef4990b826ec36cdf4226e837053
# Parent  27345a67225d0009dc46accb4fb22dc20fdc1609
Preserve aspect ratio unless config file says otherwise

diff -r 27345a67225d -r 251fe7a75a14 render_sdl.c
--- a/render_sdl.c	Tue Oct 29 00:03:11 2013 -0700
+++ b/render_sdl.c	Tue Oct 29 19:09:19 2013 -0700
@@ -5,6 +5,7 @@
 */
 #include <stdlib.h>
 #include <stdio.h>
+#include <math.h>
 #include "render.h"
 #include "blastem.h"
 #include "io.h"
@@ -101,7 +102,7 @@
 #ifndef DISABLE_OPENGL
 GLuint textures[3], buffers[2], vshader, fshader, program, un_textures[2], at_pos;
 
-const GLfloat vertex_data[] = {
+GLfloat vertex_data[] = {
 	-1.0f, -1.0f,
 	 1.0f, -1.0f,
 	-1.0f,  1.0f,
@@ -259,16 +260,25 @@
 	if (use_gl)
 	{
 		GLenum res = glewInit();
-		if (res != GLEW_OK)
-		{
+		if (res != GLEW_OK) {
 			fprintf(stderr, "Initialization of GLEW failed with code %d\n", res);
 			exit(1);
 		}
-		if (!GLEW_VERSION_2_0)
-		{
+		if (!GLEW_VERSION_2_0) {
 			fputs("OpenGL 2.0 is unable, falling back to standard SDL rendering\n", stderr);
 			exit(1);
 		}
+		float aspect = (float)width / height;
+		if (fabs(aspect - 4.0/3.0) > 0.01 && strcmp(tern_find_ptr_default(config, "videoaspect", "normal"), "stretch")) {
+			for (int i = 0; i < 4; i++)
+			{
+				if (aspect > 4.0/3.0) {
+					vertex_data[i*2] *= (4.0/3.0)/aspect;
+				} else {
+					vertex_data[i*2+1] *= aspect/(4.0/3.0);
+				}
+			}
+		}
 	}
 	render_gl = use_gl;
 #endif
diff -r 27345a67225d -r 251fe7a75a14 shaders/default.v.glsl
--- a/shaders/default.v.glsl	Tue Oct 29 00:03:11 2013 -0700
+++ b/shaders/default.v.glsl	Tue Oct 29 19:09:19 2013 -0700
@@ -6,5 +6,5 @@
 void main()
 {
 	gl_Position = vec4(pos, 0.0, 1.0);
-	texcoord = pos * vec2(320.0/1024.0, 240.0/-512.0) + vec2(320.0/1024.0, 240.0/512.0);
+	texcoord = sign(pos) * vec2(320.0/1024.0, 240.0/-512.0) + vec2(320.0/1024.0, 240.0/512.0);
 }