diff options
Diffstat (limited to 'src/texture.c')
| -rw-r--r-- | src/texture.c | 268 |
1 files changed, 268 insertions, 0 deletions
diff --git a/src/texture.c b/src/texture.c new file mode 100644 index 0000000..37e38e9 --- /dev/null +++ b/src/texture.c @@ -0,0 +1,268 @@ +#include "texture.h" + +static int honey_lua_texture_new(lua_State* L) +{ + honey_texture* texture = lua_newuserdata(L, sizeof(honey_texture)); + return 1; +} + +static int honey_lua_texture_create(lua_State* L) +{ + honey_texture* texture; + int width, height; + char* type; + honey_lua_parse_arguments(L, 4, + HONEY_USERDATA, &texture, + HONEY_STRING, &type, + HONEY_INTEGER, &width, + HONEY_INTEGER, &height); + + if (strcmp(type, "greyscale") == 0) + honey_texture_new_greyscale(texture, width, height, NULL); + else if (strcmp(type, "rgb") == 0) + honey_texture_new_rgb(texture, width, height, NULL); + else if (strcmp(type, "rgba") == 0) + honey_texture_new_rgba(texture, width, height, NULL); + else if (strcmp(type, "depth") == 0) + honey_texture_new_depth(texture, width, height, NULL); + else { + char* error; + honey_format_string(&error, + "unknown texture type '%s'", + type); + lua_pushstring(L, error); + free(error); + lua_error(L); + } + return 0; +} + +static int honey_lua_texture_load(lua_State* L) +{ + honey_texture* texture; + char* texture_path; + honey_lua_parse_arguments(L, 3, + HONEY_USERDATA, &texture, + HONEY_STRING, &texture_path); + enum honey_texture_result result = honey_texture_load(texture, texture_path); + if (result != TEXTURE_OK) { + char* error; + honey_format_string(&error, + "failed to load '%s'", + texture_path); + lua_pushstring(L, error); + free(error); + lua_error(L); + } + + return 0; +} + +static int honey_lua_texture_use(lua_State* L) +{ + honey_texture* texture; + int texture_unit; + honey_lua_parse_arguments(L, 2, + HONEY_USERDATA, &texture, + HONEY_INTEGER, &texture_unit); + honey_texture_use(*texture, texture_unit); + return 0; +} + +static int honey_lua_framebuffer_new(lua_State* L) +{ + honey_texture* draw, *depth; + if (lua_isuserdata(L, 1)) + draw = lua_touserdata(L, 1); + else + draw = NULL; + + if (lua_isuserdata(L, 2)) + depth = lua_touserdata(L, 2); + else + depth = NULL; + + int width, height; + honey_lua_parse_arguments(L, 4, HONEY_ANY, HONEY_ANY, + HONEY_INTEGER, &width, + HONEY_INTEGER, &height); + + unsigned int framebuffer; + honey_texture_framebuffer_object_new(&framebuffer, + draw, depth, + width, height); + lua_pushinteger(L, framebuffer); + return 1; +} + +void honey_setup_texture(lua_State* L) +{ + honey_lua_element texture_elements[] = { + { "new", HONEY_FUNCTION, { .function = honey_lua_texture_new } }, + { "new_framebuffer", HONEY_FUNCTION, { .function = honey_lua_framebuffer_new } }, + { "create", HONEY_FUNCTION, { .function = honey_lua_texture_create } }, + { "load", HONEY_FUNCTION, { .function = honey_lua_texture_load } }, + { "use", HONEY_FUNCTION, { .function = honey_lua_texture_use } }, + }; + + honey_lua_create_table(L, texture_elements, 5); +} + +/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ + +static void generate_texture(honey_texture* texture, + int width, int height, + int format, int type, + void* data) +{ + unsigned int texture_id; + glGenTextures(1, &texture_id); + glBindTexture(GL_TEXTURE_2D, texture_id); + + 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, GL_LINEAR); + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); + + glTexImage2D(GL_TEXTURE_2D, 0, + format, + width, height, 0, + format, + type, data); + + texture->id = texture_id; + texture->width = width; + texture->height = height; + + switch(format) { + case GL_RED: + texture->type = GREY; + texture->channels = 1; + break; + + case GL_RGB: + texture->type = RGB; + texture->channels = 3; + break; + + case GL_RGBA: + texture->type = RGBA; + texture->channels = 4; + break; + + case GL_DEPTH_COMPONENT: + texture->type = DEPTH; + texture->channels = 1; + break; + + default: + break; + } + + return HONEY_OK; +} + +/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ + +void honey_texture_new_greyscale(honey_texture* texture, + int height, int width, + unsigned char* data) +{ + generate_texture(texture, width, height, GL_RED, GL_UNSIGNED_BYTE, data); +} + +/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ + +void honey_texture_new_rgb(honey_texture* texture, + int height, int width, + unsigned char* data) +{ + generate_texture(texture, width, height, GL_RGB, GL_UNSIGNED_BYTE, data); +} + +/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ + +void honey_texture_new_rgba(honey_texture* texture, + int height, int width, + unsigned char* data) +{ + generate_texture(texture, width, height, GL_RGBA, GL_UNSIGNED_BYTE, data); +} + +/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ + +void honey_texture_new_depth(honey_texture* texture, + int height, int width, + float* data) +{ + generate_texture(texture, width, height, GL_DEPTH_COMPONENT, GL_FLOAT, data); +} + +/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ + +enum honey_texture_result honey_texture_load(honey_texture* texture, + char* texture_path) +{ + int width, height, channels; + unsigned char* image_data = stbi_load(texture_path, &width, &height, &channels, 0); + if (image_data == NULL) { + return TEXTURE_FAILED; + } + + switch(channels) { + case 1: + honey_texture_new_greyscale(texture, width, height, image_data); + break; + + case 3: + honey_texture_new_rgb(texture, width, height, image_data); + break; + + case 4: + honey_texture_new_rgba(texture, width, height, image_data); + break; + + default: + return TEXTURE_CHANNEL_ERROR; + } + + glGenerateMipmap(GL_TEXTURE_2D); + stbi_image_free(image_data); + + return TEXTURE_OK; +} + +/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ + +void honey_texture_use(honey_texture texture, int texture_unit) { + glActiveTexture(GL_TEXTURE0 + texture_unit); + glBindTexture(GL_TEXTURE_2D, texture.id); +} + +/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ + +void honey_texture_framebuffer_object_new(unsigned int* destination, + honey_texture* draw, + honey_texture* depth, + int width, int height) +{ + glBindTexture(GL_TEXTURE_2D, 0); + + glGenFramebuffers(1, destination); + glBindFramebuffer(GL_FRAMEBUFFER, *destination); + + if (draw != NULL) + glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, draw->id, 0); + else { + glDrawBuffer(GL_NONE); + glReadBuffer(GL_NONE); + } + + if (depth != NULL) + glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, depth->id, 0); + + if (glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE) + printf("framebuffer is not complete!\n"); + + glBindFramebuffer(GL_FRAMEBUFFER, 0); +} |