Steward
分享是一種喜悅、更是一種幸福
掌機 - Miyoo A30 - C/C++ - SDL v2.0 - OpenGL ES 2.0 - Use Shader
main.c
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 | #include <stdio.h> #include <stdlib.h> #include <SDL2/SDL.h> #include <GLES2/gl2.h> const char *vShaderSrc = "attribute vec4 vPosition; \n" "void main(void) \n" "{ \n" " gl_Position = vPosition; \n" "}" ; const char *fShaderSrc = "#ifdef GL_ES \n" "precision mediump float; \n" "#endif \n" "uniform vec4 vColor; \n" "void main(void) \n" "{ \n" " gl_FragColor = vColor; \n" "}" ; int main ( int argc, char **argv) { SDL_Window * window = NULL ; SDL_GLContext context = {0}; SDL_Init ( SDL_INIT_VIDEO ); SDL_GL_SetAttribute ( SDL_GL_CONTEXT_PROFILE_MASK , SDL_GL_CONTEXT_PROFILE_ES ); SDL_GL_SetAttribute ( SDL_GL_CONTEXT_MAJOR_VERSION , 2); SDL_GL_SetAttribute ( SDL_GL_CONTEXT_MINOR_VERSION , 0); window = SDL_CreateWindow ( "main" , 0, 0, 320, 240, SDL_WINDOW_OPENGL ); context = SDL_GL_CreateContext ( window ); GLuint vShader = 0; GLuint fShader = 0; GLuint pObject = 0; vShader = glCreateShader ( GL_VERTEX_SHADER ); glShaderSource (vShader, 1, &vShaderSrc, NULL ); glCompileShader (vShader); fShader = glCreateShader ( GL_FRAGMENT_SHADER ); glShaderSource (fShader, 1, &fShaderSrc, NULL ); glCompileShader (fShader); pObject = glCreateProgram (); glAttachShader (pObject, vShader); glAttachShader (pObject, fShader); glLinkProgram (pObject); glUseProgram (pObject); GLfloat v[] = { 0.0f, 0.5f, 0.0f, -0.5f, -0.5f, 0.0f, 0.5f, -0.5f, 0.0f }; GLuint vp = glGetAttribLocation (pObject, "vPosition" ); glVertexAttribPointer (vp, 3, GL_FLOAT , GL_FALSE , 0, v); glEnableVertexAttribArray (vp); GLuint vc = glGetUniformLocation (pObject, "vColor" ); glUniform4f (vc, 1.0f, 0.0f, 0.0f, 1.0f); glViewport (0, 0, 320, 240); glClear ( GL_COLOR_BUFFER_BIT ); glDrawArrays ( GL_TRIANGLES , 0, 3); SDL_GL_SwapWindow ( window ); SDL_Delay (30000); SDL_DestroyWindow ( window ); SDL_GL_DeleteContext ( context ); SDL_Quit (); return 0; } |
編譯、執行
$ /opt/a30/bin/arm-linux-gcc \ -I/opt/a30/arm-a30-linux-gnueabihf/sysroot/usr/include/SDL2 \ -lSDL2 -lSDL2_gfx -lSDL2_image -lSDL2_ttf -lSDL2_mixer \ -lGLESv2 main.c -o main /mnt/SDCARD# export LD_LIBRARY_PATH=.:/config/lib:/customer/lib:/usr/miyoo/lib /mnt/SDCARD# ./main