Mercurial > hg > ascension / file comparison

comparison: src/shader.c

src/shader.c

changeset 77
2187a732f4d7
parent 50
d8d2e4817db1
equal deleted inserted replaced
76:eb16be99b0ad 77:2187a732f4d7
24 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 24 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
25 * POSSIBILITY OF SUCH DAMAGE. 25 * POSSIBILITY OF SUCH DAMAGE.
26 */ 26 */
27 27
28 #include "ascension/shader.h" 28 #include "ascension/shader.h"
29 #include "ascension/files.h"
30 #include "ascension/error.h" 29 #include "ascension/error.h"
31 30
32 #include <GL/glew.h> 31 #include <GL/glew.h>
33 #include <string.h> 32 #include <string.h>
34 33
35 AscShader asc_shader_compile(unsigned int type, 34 /**
36 char const *code, 35 * Compiles a shader from the given source code.
37 int length) { 36 *
37 * The ID of the returned shader will be zero when something went wrong.
38 *
39 * @param type the shader type (use the GL enum)
40 * @param code the source code
41 * @return the compiled shader
42 */
43 static unsigned asc_shader_compile(unsigned int type, char const *code) {
38 GLuint id = glCreateShader(type); 44 GLuint id = glCreateShader(type);
39 if (id == 0) { 45 if (id == 0) {
40 asc_error("glCreateShader failed"); 46 asc_error("glCreateShader failed");
41 return (AscShader) {0}; 47 return 0;
42 } 48 }
43 49
44 GLint success; 50 GLint success;
51 int length = (int) strlen(code); // must be int because of OpenGL API
45 glShaderSource(id, 1, &code, &length); 52 glShaderSource(id, 1, &code, &length);
46 glCompileShader(id); 53 glCompileShader(id);
47 glGetShaderiv(id, GL_COMPILE_STATUS, &success); 54 glGetShaderiv(id, GL_COMPILE_STATUS, &success);
48 if (success) { 55 if (success) {
49 asc_dprintf("Shader %u compiled", id); 56 asc_dprintf("Shader %u compiled", id);
50 return (AscShader) {id}; 57 return id;
51 } else { 58 } else {
52 char *log = malloc(1024); 59 char *log = malloc(1024);
53 glGetShaderInfoLog(id, 1024, NULL, log); 60 glGetShaderInfoLog(id, 1024, NULL, log);
54 glDeleteShader(id); 61 glDeleteShader(id);
55 asc_error(log); 62 asc_error(log);
56 free(log); 63 free(log);
57 return (AscShader) {0}; 64 return 0;
58 } 65 }
59 } 66 }
60 67
61 AscShader asc_shader_compilef(unsigned int type, 68 /**
62 char const *filename) { 69 * This function links shaders into a program.
63 asc_file code = asc_file_mmap_rdonly(filename); 70 *
64 if (code.ptr == NULL) { 71 * The ID of the returned program will be zero when something went wrong.
65 asc_error("Mapping shader file into memory failed"); 72 *
66 return (AscShader) {0}; 73 * @param shader the shader IDs to link
67 } 74 * @param n the number of shaders
68 AscShader ret = asc_shader_compile(type, code.ptr, code.length); 75 * @return a compiled program
69 asc_file_unmap(code); 76 */
70 return ret; 77 static AscShaderProgram asc_shader_link(unsigned shader[], unsigned n) {
71 }
72
73 AscShaderProgram asc_shader_link(AscShader vertex,
74 AscShader fragment) {
75 if (vertex.id == 0 || fragment.id == 0) {
76 asc_dprintf("Skip linking shader program - shaders have not been loaded correctly.");
77 return (AscShaderProgram) {0};
78 }
79
80 GLint success; 78 GLint success;
81 GLint id = glCreateProgram(); 79 GLint id = glCreateProgram();
82 if (id <= 0) { 80 if (id <= 0) {
83 asc_error("glCreateProgram failed"); 81 asc_error("glCreateProgram failed");
84 return (AscShaderProgram) {0}; 82 return (AscShaderProgram) {0};
85 } 83 }
86 glAttachShader(id, vertex.id); 84 for (unsigned i = 0; i < n; i++) {
87 glAttachShader(id, fragment.id); 85 glAttachShader(id, shader[i]);
86 }
88 glLinkProgram(id); 87 glLinkProgram(id);
89 glGetProgramiv(id, GL_LINK_STATUS, &success); 88 glGetProgramiv(id, GL_LINK_STATUS, &success);
90 glDetachShader(id, vertex.id); 89 for (unsigned i = 0; i < n; i++) {
91 glDetachShader(id, fragment.id); 90 glDeleteShader(shader[i]);
91 }
92 if (success) { 92 if (success) {
93 asc_dprintf("Shader Program %u linked (vtf: %u, frag: %u)", id, vertex.id, fragment.id); 93 asc_dprintf("Shader Program %u linked.", id);
94 AscShaderProgram prog; 94 AscShaderProgram prog;
95 prog.id = id; 95 prog.id = id;
96 // TODO: maybe not every program has the same uniforms
96 prog.model = glGetUniformLocation(id, "model"); 97 prog.model = glGetUniformLocation(id, "model");
97 prog.view = glGetUniformLocation(id, "view"); 98 prog.view = glGetUniformLocation(id, "view");
98 prog.projection = glGetUniformLocation(id, "projection"); 99 prog.projection = glGetUniformLocation(id, "projection");
99 return prog; 100 return prog;
100 } else { 101 } else {
101 char *log = malloc(1024); 102 char *log = malloc(1024);
102 glGetProgramInfoLog(id, 1024, NULL, log); 103 glGetProgramInfoLog(id, 1024, NULL, log);
103 glDeleteShader(id); 104 glDeleteProgram(id);
104 asc_error(log); 105 asc_error(log);
105 free(log); 106 free(log);
106 return (AscShaderProgram) {0}; 107 return (AscShaderProgram) {0};
107 } 108 }
108 }
109
110 void asc_shader_destroy(AscShader shader) {
111 if (shader.id > 0) {
112 asc_dprintf("Delete Shader %u", shader.id);
113 glDeleteShader(shader.id);
114 }
115 shader.id = 0;
116 } 109 }
117 110
118 void asc_shader_program_destroy(AscShaderProgram program) { 111 void asc_shader_program_destroy(AscShaderProgram program) {
119 if (program.id > 0) { 112 if (program.id > 0) {
120 asc_dprintf("Delete Shader Program %u", program.id); 113 asc_dprintf("Delete Shader Program %u", program.id);
121 glDeleteProgram(program.id); 114 glDeleteProgram(program.id);
122 } 115 }
123 program.id = 0; 116 program.id = 0;
124 } 117 }
125 118
126 AscShaderProgram asc_shader_easy_compile_and_link( 119 AscShaderProgram asc_shader_program_create(AscShaderCodes codes) {
127 char const *vtxName, char const *fragName) { 120 unsigned shader[4];
128 AscShader font_vtx = asc_shader_compilef(GL_VERTEX_SHADER, vtxName); 121 unsigned n = 0;
129 AscShader font_frag = asc_shader_compilef(GL_FRAGMENT_SHADER, fragName); 122 if (codes.vtx) {
130 AscShaderProgram prog = asc_shader_link(font_vtx, font_frag); 123 shader[n++] = asc_shader_compile(GL_VERTEX_SHADER, codes.vtx);
131 asc_shader_destroy(font_vtx); 124 }
132 asc_shader_destroy(font_frag); 125 if (codes.frag) {
126 shader[n++] = asc_shader_compile(GL_FRAGMENT_SHADER, codes.frag);
127 }
128 const AscShaderProgram prog = asc_shader_link(shader, n);
129 for (unsigned i = 0; i < n; i++) {
130 glDeleteShader(shader[i]);
131 }
133 return prog; 132 return prog;
134 } 133 }

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