/** * Test multi-texturing with GL shading language. * * Copyright (C) 2008 Brian Paul All Rights Reserved. * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the "Software"), * to deal in the Software without restriction, including without limitation * the rights to use, copy, modify, merge, publish, distribute, sublicense, * and/or sell copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included * in all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ #include #include #include #include #include #include "GL/glut.h" #include "readtex.h" #include "extfuncs.h" #include "shaderutil.h" static const char *Demo = "multitex"; static const char *VertFile = "multitex.vert"; static const char *FragFile = "multitex.frag"; static const char *TexFiles[2] = { "../images/tile.rgb", "../images/tree2.rgba" }; static GLuint Program; static GLfloat Xrot = -90.0, Yrot = .0, Zrot = 0.0; static GLfloat EyeDist = 10; static GLboolean Anim = GL_TRUE; /* value[0] = tex unit */ static struct uniform_info Uniforms[] = { { "tex1", 1, GL_INT, { 0, 0, 0, 0 }, -1 }, { "tex2", 1, GL_INT, { 1, 0, 0, 0 }, -1 }, END_OF_UNIFORMS }; static void DrawPolygon(GLfloat size) { glPushMatrix(); glRotatef(90, 1, 0, 0); glNormal3f(0, 0, 1); glBegin(GL_POLYGON); glMultiTexCoord2f(GL_TEXTURE0, 0, 0); glMultiTexCoord2f(GL_TEXTURE1, 0, 0); glVertex2f(-size, -size); glMultiTexCoord2f(GL_TEXTURE0, 2, 0); glMultiTexCoord2f(GL_TEXTURE1, 1, 0); glVertex2f( size, -size); glMultiTexCoord2f(GL_TEXTURE0, 2, 2); glMultiTexCoord2f(GL_TEXTURE1, 1, 1); glVertex2f( size, size); glMultiTexCoord2f(GL_TEXTURE0, 0, 2); glMultiTexCoord2f(GL_TEXTURE1, 0, 1); glVertex2f(-size, size); glEnd(); glPopMatrix(); } static void draw(void) { glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); glPushMatrix(); /* modelview matrix */ glTranslatef(0.0, 0.0, -EyeDist); glRotatef(Zrot, 0, 0, 1); glRotatef(Yrot, 0, 1, 0); glRotatef(Xrot, 1, 0, 0); DrawPolygon(3.0); glPopMatrix(); glutSwapBuffers(); } static void idle(void) { GLfloat t = 0.05 * glutGet(GLUT_ELAPSED_TIME); Yrot = t; glutPostRedisplay(); } static void key(unsigned char k, int x, int y) { (void) x; (void) y; switch (k) { case ' ': case 'a': Anim = !Anim; if (Anim) glutIdleFunc(idle); else glutIdleFunc(NULL); break; case 'z': EyeDist -= 0.5; if (EyeDist < 3.0) EyeDist = 3.0; break; case 'Z': EyeDist += 0.5; if (EyeDist > 90.0) EyeDist = 90; break; case 27: exit(0); } glutPostRedisplay(); } static void specialkey(int key, int x, int y) { GLfloat step = 2.0; (void) x; (void) y; switch (key) { case GLUT_KEY_UP: Xrot += step; break; case GLUT_KEY_DOWN: Xrot -= step; break; case GLUT_KEY_LEFT: Yrot -= step; break; case GLUT_KEY_RIGHT: Yrot += step; break; } glutPostRedisplay(); } /* new window size or exposure */ static void Reshape(int width, int height) { GLfloat ar = (float) width / (float) height; glViewport(0, 0, (GLint)width, (GLint)height); glMatrixMode(GL_PROJECTION); glLoadIdentity(); glFrustum(-2.0*ar, 2.0*ar, -2.0, 2.0, 4.0, 100.0); glMatrixMode(GL_MODELVIEW); glLoadIdentity(); } static void InitTextures(void) { GLenum filter = GL_LINEAR; int i; for (i = 0; i < 2; i++) { GLint imgWidth, imgHeight; GLenum imgFormat; GLubyte *image = NULL; image = LoadRGBImage(TexFiles[i], &imgWidth, &imgHeight, &imgFormat); if (!image) { printf("Couldn't read %s\n", TexFiles[i]); exit(0); } glActiveTexture(GL_TEXTURE0 + i); glBindTexture(GL_TEXTURE_2D, 42 + i); gluBuild2DMipmaps(GL_TEXTURE_2D, 4, imgWidth, imgHeight, imgFormat, GL_UNSIGNED_BYTE, image); free(image); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, filter); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, filter); } } static GLuint CreateProgram(const char *vertProgFile, const char *fragProgFile, struct uniform_info *uniforms) { GLuint fragShader, vertShader, program; vertShader = CompileShaderFile(GL_VERTEX_SHADER, vertProgFile); fragShader = CompileShaderFile(GL_FRAGMENT_SHADER, fragProgFile); assert(vertShader); program = LinkShaders(vertShader, fragShader); glUseProgram_func(program); InitUniforms(program, uniforms); return program; } static void InitPrograms(void) { Program = CreateProgram(VertFile, FragFile, Uniforms); } static void InitGL(void) { const char *version = (const char *) glGetString(GL_VERSION); if (version[0] != '2' || version[1] != '.') { printf("Warning: this program expects OpenGL 2.0\n"); /*exit(1);*/ } printf("GL_RENDERER = %s\n",(const char *) glGetString(GL_RENDERER)); GetExtensionFuncs(); InitTextures(); InitPrograms(); glEnable(GL_DEPTH_TEST); glClearColor(.6, .6, .9, 0); glColor3f(1.0, 1.0, 1.0); } int main(int argc, char *argv[]) { glutInit(&argc, argv); glutInitWindowSize(500, 400); glutInitDisplayMode(GLUT_RGB | GLUT_DEPTH | GLUT_DOUBLE); glutCreateWindow(Demo); glutReshapeFunc(Reshape); glutKeyboardFunc(key); glutSpecialFunc(specialkey); glutDisplayFunc(draw); if (Anim) glutIdleFunc(idle); InitGL(); glutMainLoop(); return 0; }