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-rw-r--r--progs/glsl/shadow_sampler.c341
1 files changed, 341 insertions, 0 deletions
diff --git a/progs/glsl/shadow_sampler.c b/progs/glsl/shadow_sampler.c
new file mode 100644
index 00000000000..2902b535522
--- /dev/null
+++ b/progs/glsl/shadow_sampler.c
@@ -0,0 +1,341 @@
+/**
+ * Test shadow2DRectProj() and shadow2D() functions.
+ * Brian Paul
+ * 11 April 2007
+ */
+
+#define GL_GLEXT_PROTOTYPES
+#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"
+
+
+/** Use GL_RECTANGLE texture (with projective texcoords)? */
+#define USE_RECT 01
+
+#define TEXSIZE 16
+
+
+static char *FragProgFile = NULL;
+static char *VertProgFile = NULL;
+
+static GLuint fragShader;
+static GLuint vertShader;
+static GLuint program;
+
+static GLint uTexture2D;
+static GLint uTextureRect;
+
+static GLint win = 0;
+
+static GLenum Filter = GL_LINEAR;
+
+static void
+CheckError(int line)
+{
+ GLenum err = glGetError();
+ if (err) {
+ printf("GL Error %s (0x%x) at line %d\n",
+ gluErrorString(err), (int) err, line);
+ }
+}
+
+
+static void
+PrintString(const char *s)
+{
+ while (*s) {
+ glutBitmapCharacter(GLUT_BITMAP_8_BY_13, (int) *s);
+ s++;
+ }
+}
+
+
+static void
+Redisplay(void)
+{
+ CheckError(__LINE__);
+ glClear(GL_COLOR_BUFFER_BIT);
+
+ glPushMatrix();
+
+ CheckError(__LINE__);
+ glUseProgram_func(program);
+ CheckError(__LINE__);
+
+ glBegin(GL_POLYGON);
+#if USE_RECT
+ /* scale coords by two to test projection */
+ glTexCoord4f( 0, 0, 0, 2.0); glVertex2f(-1, -1);
+ glTexCoord4f(2*TEXSIZE, 0, 2*1, 2.0); glVertex2f( 1, -1);
+ glTexCoord4f(2*TEXSIZE, 2*TEXSIZE, 2*1, 2.0); glVertex2f( 1, 1);
+ glTexCoord4f( 0, 2*TEXSIZE, 0, 2.0); glVertex2f(-1, 1);
+#else
+ glTexCoord3f(0, 0, 0); glVertex2f(-1, -1);
+ glTexCoord3f(1, 0, 1); glVertex2f( 1, -1);
+ glTexCoord3f(1, 1, 1); glVertex2f( 1, 1);
+ glTexCoord3f(0, 1, 0); glVertex2f(-1, 1);
+#endif
+ glEnd();
+
+ glPopMatrix();
+
+ glUseProgram_func(0);
+ glWindowPos2iARB(80, 20);
+ PrintString("white black white black");
+
+ glutSwapBuffers();
+}
+
+
+static void
+Reshape(int width, int height)
+{
+ glViewport(0, 0, width, height);
+ glMatrixMode(GL_PROJECTION);
+ glLoadIdentity();
+ glFrustum(-1.0, 1.0, -1.0, 1.0, 5.0, 25.0);
+ glMatrixMode(GL_MODELVIEW);
+ glLoadIdentity();
+ glTranslatef(0.0f, 0.0f, -8.0f);
+}
+
+
+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)
+{
+ GLfloat image[TEXSIZE][TEXSIZE];
+ GLuint i, j;
+
+ for (i = 0; i < TEXSIZE; i++) {
+ for (j = 0; j < TEXSIZE; j++) {
+ if (j < (TEXSIZE / 2)) {
+ image[i][j] = 0.25;
+ }
+ else {
+ image[i][j] = 0.75;
+ }
+ }
+ }
+
+ glActiveTexture(GL_TEXTURE0); /* unit 0 */
+ glBindTexture(GL_TEXTURE_2D, 42);
+ glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT, TEXSIZE, TEXSIZE, 0,
+ GL_DEPTH_COMPONENT, GL_FLOAT, image);
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAX_LEVEL, 1);
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, Filter);
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, Filter);
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_COMPARE_MODE_ARB,
+ GL_COMPARE_R_TO_TEXTURE_ARB);
+ CheckError(__LINE__);
+
+ glActiveTexture(GL_TEXTURE1); /* unit 1 */
+ glBindTexture(GL_TEXTURE_RECTANGLE_ARB, 43);
+ glTexImage2D(GL_TEXTURE_RECTANGLE_ARB, 0, GL_DEPTH_COMPONENT,
+ TEXSIZE, 10, 0,/*16x10*/
+ GL_DEPTH_COMPONENT, GL_FLOAT, image);
+ glTexParameteri(GL_TEXTURE_RECTANGLE_ARB, GL_TEXTURE_MIN_FILTER, Filter);
+ glTexParameteri(GL_TEXTURE_RECTANGLE_ARB, GL_TEXTURE_MAG_FILTER, Filter);
+ glTexParameteri(GL_TEXTURE_RECTANGLE_ARB, GL_TEXTURE_COMPARE_MODE_ARB,
+ GL_COMPARE_R_TO_TEXTURE_ARB);
+ CheckError(__LINE__);
+}
+
+
+static void
+LoadAndCompileShader(GLuint shader, const char *text)
+{
+ GLint stat;
+ glShaderSource_func(shader, 1, (const GLchar **) &text, NULL);
+ glCompileShader_func(shader);
+ glGetShaderiv_func(shader, GL_COMPILE_STATUS, &stat);
+ if (!stat) {
+ GLchar log[1000];
+ GLsizei len;
+ glGetShaderInfoLog_func(shader, 1000, &len, log);
+ fprintf(stderr, "fslight: problem compiling shader:\n%s\n", log);
+ exit(1);
+ }
+}
+
+
+/**
+ * Read a shader from a file.
+ */
+static void
+ReadShader(GLuint shader, const char *filename)
+{
+ const int max = 100*1000;
+ int n;
+ char *buffer = (char*) malloc(max);
+ FILE *f = fopen(filename, "r");
+ if (!f) {
+ fprintf(stderr, "fslight: Unable to open shader file %s\n", filename);
+ exit(1);
+ }
+
+ n = fread(buffer, 1, max, f);
+ printf("fslight: read %d bytes from shader file %s\n", n, filename);
+ if (n > 0) {
+ buffer[n] = 0;
+ LoadAndCompileShader(shader, buffer);
+ }
+
+ fclose(f);
+ free(buffer);
+}
+
+
+static void
+CheckLink(GLuint prog)
+{
+ GLint stat;
+ glGetProgramiv_func(prog, GL_LINK_STATUS, &stat);
+ if (!stat) {
+ GLchar log[1000];
+ GLsizei len;
+ glGetProgramInfoLog_func(prog, 1000, &len, log);
+ fprintf(stderr, "Linker error:\n%s\n", log);
+ }
+}
+
+
+static void
+Init(void)
+{
+ static const char *fragShaderText =
+ "uniform sampler2DShadow shadowTex2D; \n"
+ "uniform sampler2DRectShadow shadowTexRect; \n"
+ "void main() {\n"
+#if USE_RECT
+ " gl_FragColor = shadow2DRectProj(shadowTexRect, gl_TexCoord[0]); \n"
+#else
+ " gl_FragColor = shadow2D(shadowTex2D, gl_TexCoord[0].xyz); \n"
+#endif
+ "}\n";
+ static const char *vertShaderText =
+ "void main() {\n"
+ " gl_Position = gl_ModelViewProjectionMatrix * gl_Vertex;\n"
+ " gl_TexCoord[0] = gl_MultiTexCoord0; \n"
+ "}\n";
+ const char *version;
+
+#if USE_RECT
+ if (!glutExtensionSupported("GL_ARB_texture_rectangle")) {
+ printf("This program requires GL_ARB_texture_rectangle\n");
+ exit(1);
+ }
+#endif
+
+ version = (const char *) glGetString(GL_VERSION);
+ if (version[0] != '2' || version[1] != '.') {
+ printf("This program requires OpenGL 2.x, found %s\n", version);
+ exit(1);
+ }
+ printf("GL_RENDERER = %s\n",(const char *) glGetString(GL_RENDERER));
+
+ GetExtensionFuncs();
+
+ fragShader = glCreateShader_func(GL_FRAGMENT_SHADER);
+ if (FragProgFile)
+ ReadShader(fragShader, FragProgFile);
+ else
+ LoadAndCompileShader(fragShader, fragShaderText);
+
+ vertShader = glCreateShader_func(GL_VERTEX_SHADER);
+ if (VertProgFile)
+ ReadShader(vertShader, VertProgFile);
+ else
+ LoadAndCompileShader(vertShader, vertShaderText);
+
+ program = glCreateProgram_func();
+ glAttachShader_func(program, fragShader);
+ glAttachShader_func(program, vertShader);
+ glLinkProgram_func(program);
+ CheckLink(program);
+ glUseProgram_func(program);
+
+ uTexture2D = glGetUniformLocation_func(program, "shadowTex2D");
+ uTextureRect = glGetUniformLocation_func(program, "shadowTexRect");
+ printf("uTexture2D %d uTextureRect %d\n", uTexture2D, uTextureRect);
+ if (uTexture2D >= 0) {
+ glUniform1i_func(uTexture2D, 0); /* use texture unit 0 */
+ }
+ if (uTextureRect >= 0) {
+ glUniform1i_func(uTextureRect, 1); /* use texture unit 0 */
+ }
+ CheckError(__LINE__);
+
+ glClearColor(0.3f, 0.3f, 0.3f, 0.0f);
+ glColor3f(1, 1, 1);
+
+ MakeTexture();
+ CheckError(__LINE__);
+}
+
+
+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(400, 300);
+ glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE);
+ win = glutCreateWindow(argv[0]);
+ glutReshapeFunc(Reshape);
+ glutKeyboardFunc(Key);
+ glutDisplayFunc(Redisplay);
+ ParseOptions(argc, argv);
+ Init();
+ glutMainLoop();
+ return 0;
+}
+
+
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