--- /dev/null
+/**
+ * Test GLSL 1.20 gl_PointCoord fragment program attribute.
+ * Brian Paul
+ * 11 Aug 2007
+ */
+
+
+#include <assert.h>
+#include <string.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+#include <GL/gl.h>
+#include <GL/glut.h>
+#include <GL/glext.h>
+#include "extfuncs.h"
+#include "shaderutil.h"
+
+
+static GLint WinWidth = 300, WinHeight = 300;
+static char *FragProgFile = NULL;
+static char *VertProgFile = NULL;
+static GLuint fragShader;
+static GLuint vertShader;
+static GLuint program;
+static GLint win = 0;
+static GLint tex0;
+static GLenum Filter = GL_NEAREST;
+
+
+static void
+Redisplay(void)
+{
+ glClear(GL_COLOR_BUFFER_BIT);
+
+ /* draw one point/sprite */
+ glPushMatrix();
+ glPointSize(60);
+ glBegin(GL_POINTS);
+ glVertex2f(WinWidth / 2.0f, WinHeight / 2.0f);
+ glEnd();
+ glPopMatrix();
+
+ glutSwapBuffers();
+}
+
+
+static void
+Reshape(int width, int height)
+{
+ glViewport(0, 0, width, height);
+ glMatrixMode(GL_PROJECTION);
+ glLoadIdentity();
+ glOrtho(0, width, 0, height, -1, 1);
+
+ glMatrixMode(GL_MODELVIEW);
+ glLoadIdentity();
+
+ WinWidth = width;
+ WinHeight = height;
+}
+
+
+static void
+CleanUp(void)
+{
+ glDeleteShader_func(fragShader);
+ glDeleteShader_func(vertShader);
+ glDeleteProgram_func(program);
+ glutDestroyWindow(win);
+}
+
+
+static void
+Key(unsigned char key, int x, int y)
+{
+ (void) x;
+ (void) y;
+
+ switch(key) {
+ case 27:
+ CleanUp();
+ exit(0);
+ break;
+ }
+ glutPostRedisplay();
+}
+
+
+
+static void
+MakeTexture(void)
+{
+#define SZ 16
+ GLubyte image[SZ][SZ][4];
+ GLuint i, j;
+
+ for (i = 0; i < SZ; i++) {
+ for (j = 0; j < SZ; j++) {
+ if ((i + j) & 1) {
+ image[i][j][0] = 0;
+ image[i][j][1] = 0;
+ image[i][j][2] = 0;
+ image[i][j][3] = 255;
+ }
+ else {
+ image[i][j][0] = j * 255 / (SZ-1);
+ image[i][j][1] = i * 255 / (SZ-1);
+ image[i][j][2] = 0;
+ image[i][j][3] = 255;
+ }
+ }
+ }
+
+ glActiveTexture(GL_TEXTURE0); /* unit 0 */
+ glBindTexture(GL_TEXTURE_2D, 42);
+ glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, SZ, SZ, 0,
+ GL_RGBA, GL_UNSIGNED_BYTE, image);
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, Filter);
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, Filter);
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+#undef SZ
+}
+
+
+static void
+Init(void)
+{
+ static const char *fragShaderText =
+ "#version 120 \n"
+ "uniform sampler2D tex0; \n"
+ "void main() { \n"
+ " gl_FragColor = texture2D(tex0, gl_PointCoord.xy, 0.0); \n"
+ "}\n";
+ static const char *vertShaderText =
+ "void main() {\n"
+ " gl_Position = gl_ModelViewProjectionMatrix * gl_Vertex;\n"
+ "}\n";
+
+ if (!ShadersSupported())
+ exit(1);
+
+ GetExtensionFuncs();
+
+ vertShader = CompileShaderText(GL_VERTEX_SHADER, vertShaderText);
+ fragShader = CompileShaderText(GL_FRAGMENT_SHADER, fragShaderText);
+ program = LinkShaders(vertShader, fragShader);
+
+ glUseProgram_func(program);
+
+ tex0 = glGetUniformLocation_func(program, "tex0");
+ printf("Uniforms: tex0: %d\n", tex0);
+
+ glUniform1i_func(tex0, 0); /* tex unit 0 */
+
+ /*assert(glGetError() == 0);*/
+
+ glClearColor(0.3f, 0.3f, 0.3f, 0.0f);
+
+ printf("GL_RENDERER = %s\n",(const char *) glGetString(GL_RENDERER));
+
+ assert(glIsProgram_func(program));
+ assert(glIsShader_func(fragShader));
+ assert(glIsShader_func(vertShader));
+
+ MakeTexture();
+
+ glEnable(GL_POINT_SPRITE);
+
+ glColor3f(1, 0, 0);
+}
+
+
+static void
+ParseOptions(int argc, char *argv[])
+{
+ int i;
+ for (i = 1; i < argc; i++) {
+ if (strcmp(argv[i], "-fs") == 0) {
+ FragProgFile = argv[i+1];
+ }
+ else if (strcmp(argv[i], "-vs") == 0) {
+ VertProgFile = argv[i+1];
+ }
+ }
+}
+
+
+int
+main(int argc, char *argv[])
+{
+ glutInit(&argc, argv);
+ glutInitWindowPosition( 0, 0);
+ glutInitWindowSize(WinWidth, WinHeight);
+ glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE);
+ win = glutCreateWindow(argv[0]);
+ glutReshapeFunc(Reshape);
+ glutKeyboardFunc(Key);
+ glutDisplayFunc(Redisplay);
+ ParseOptions(argc, argv);
+ Init();
+ glutMainLoop();
+ return 0;
+}