graphics/gpu/textured_cube/source/main.c

#include <3ds.h>
#include <citro3d.h>
#include <tex3ds.h>
#include <string.h>
#include "vshader_shbin.h"
#include "kitten_t3x.h"
 
#define CLEAR_COLOR 0x68B0D8FF
 
#define DISPLAY_TRANSFER_FLAGS \
 (GX_TRANSFER_FLIP_VERT(0) | GX_TRANSFER_OUT_TILED(0) | GX_TRANSFER_RAW_COPY(0) | \
 GX_TRANSFER_IN_FORMAT(GX_TRANSFER_FMT_RGBA8) | GX_TRANSFER_OUT_FORMAT(GX_TRANSFER_FMT_RGB8) | \
 GX_TRANSFER_SCALING(GX_TRANSFER_SCALE_NO))
 
typedef struct { float position[3]; float texcoord[2]; float normal[3]; } vertex;
 
static const vertex vertex_list[] =
{
 // First face (PZ)
 // First triangle
 { {-0.5f, -0.5f, +0.5f}, {0.0f, 0.0f}, {0.0f, 0.0f, +1.0f} },
 { {+0.5f, -0.5f, +0.5f}, {1.0f, 0.0f}, {0.0f, 0.0f, +1.0f} },
 { {+0.5f, +0.5f, +0.5f}, {1.0f, 1.0f}, {0.0f, 0.0f, +1.0f} },
 // Second triangle
 { {+0.5f, +0.5f, +0.5f}, {1.0f, 1.0f}, {0.0f, 0.0f, +1.0f} },
 { {-0.5f, +0.5f, +0.5f}, {0.0f, 1.0f}, {0.0f, 0.0f, +1.0f} },
 { {-0.5f, -0.5f, +0.5f}, {0.0f, 0.0f}, {0.0f, 0.0f, +1.0f} },
 
 // Second face (MZ)
 // First triangle
 { {-0.5f, -0.5f, -0.5f}, {0.0f, 0.0f}, {0.0f, 0.0f, -1.0f} },
 { {-0.5f, +0.5f, -0.5f}, {1.0f, 0.0f}, {0.0f, 0.0f, -1.0f} },
 { {+0.5f, +0.5f, -0.5f}, {1.0f, 1.0f}, {0.0f, 0.0f, -1.0f} },
 // Second triangle
 { {+0.5f, +0.5f, -0.5f}, {1.0f, 1.0f}, {0.0f, 0.0f, -1.0f} },
 { {+0.5f, -0.5f, -0.5f}, {0.0f, 1.0f}, {0.0f, 0.0f, -1.0f} },
 { {-0.5f, -0.5f, -0.5f}, {0.0f, 0.0f}, {0.0f, 0.0f, -1.0f} },
 
 // Third face (PX)
 // First triangle
 { {+0.5f, -0.5f, -0.5f}, {0.0f, 0.0f}, {+1.0f, 0.0f, 0.0f} },
 { {+0.5f, +0.5f, -0.5f}, {1.0f, 0.0f}, {+1.0f, 0.0f, 0.0f} },
 { {+0.5f, +0.5f, +0.5f}, {1.0f, 1.0f}, {+1.0f, 0.0f, 0.0f} },
 // Second triangle
 { {+0.5f, +0.5f, +0.5f}, {1.0f, 1.0f}, {+1.0f, 0.0f, 0.0f} },
 { {+0.5f, -0.5f, +0.5f}, {0.0f, 1.0f}, {+1.0f, 0.0f, 0.0f} },
 { {+0.5f, -0.5f, -0.5f}, {0.0f, 0.0f}, {+1.0f, 0.0f, 0.0f} },
 
 // Fourth face (MX)
 // First triangle
 { {-0.5f, -0.5f, -0.5f}, {0.0f, 0.0f}, {-1.0f, 0.0f, 0.0f} },
 { {-0.5f, -0.5f, +0.5f}, {1.0f, 0.0f}, {-1.0f, 0.0f, 0.0f} },
 { {-0.5f, +0.5f, +0.5f}, {1.0f, 1.0f}, {-1.0f, 0.0f, 0.0f} },
 // Second triangle
 { {-0.5f, +0.5f, +0.5f}, {1.0f, 1.0f}, {-1.0f, 0.0f, 0.0f} },
 { {-0.5f, +0.5f, -0.5f}, {0.0f, 1.0f}, {-1.0f, 0.0f, 0.0f} },
 { {-0.5f, -0.5f, -0.5f}, {0.0f, 0.0f}, {-1.0f, 0.0f, 0.0f} },
 
 // Fifth face (PY)
 // First triangle
 { {-0.5f, +0.5f, -0.5f}, {0.0f, 0.0f}, {0.0f, +1.0f, 0.0f} },
 { {-0.5f, +0.5f, +0.5f}, {1.0f, 0.0f}, {0.0f, +1.0f, 0.0f} },
 { {+0.5f, +0.5f, +0.5f}, {1.0f, 1.0f}, {0.0f, +1.0f, 0.0f} },
 // Second triangle
 { {+0.5f, +0.5f, +0.5f}, {1.0f, 1.0f}, {0.0f, +1.0f, 0.0f} },
 { {+0.5f, +0.5f, -0.5f}, {0.0f, 1.0f}, {0.0f, +1.0f, 0.0f} },
 { {-0.5f, +0.5f, -0.5f}, {0.0f, 0.0f}, {0.0f, +1.0f, 0.0f} },
 
 // Sixth face (MY)
 // First triangle
 { {-0.5f, -0.5f, -0.5f}, {0.0f, 0.0f}, {0.0f, -1.0f, 0.0f} },
 { {+0.5f, -0.5f, -0.5f}, {1.0f, 0.0f}, {0.0f, -1.0f, 0.0f} },
 { {+0.5f, -0.5f, +0.5f}, {1.0f, 1.0f}, {0.0f, -1.0f, 0.0f} },
 // Second triangle
 { {+0.5f, -0.5f, +0.5f}, {1.0f, 1.0f}, {0.0f, -1.0f, 0.0f} },
 { {-0.5f, -0.5f, +0.5f}, {0.0f, 1.0f}, {0.0f, -1.0f, 0.0f} },
 { {-0.5f, -0.5f, -0.5f}, {0.0f, 0.0f}, {0.0f, -1.0f, 0.0f} },
};
 
#define vertex_list_count (sizeof(vertex_list)/sizeof(vertex_list[0]))
 
static DVLB_s* vshader_dvlb;
static shaderProgram_s program;
static int uLoc_projection, uLoc_modelView;
static int uLoc_lightVec, uLoc_lightHalfVec, uLoc_lightClr, uLoc_material;
static C3D_Mtx projection;
static C3D_Mtx material =
{
 {
 { { 0.0f, 0.2f, 0.2f, 0.2f } }, // Ambient
 { { 0.0f, 0.4f, 0.4f, 0.4f } }, // Diffuse
 { { 0.0f, 0.8f, 0.8f, 0.8f } }, // Specular
 { { 1.0f, 0.0f, 0.0f, 0.0f } }, // Emission
 }
};
 
static void* vbo_data;
static C3D_Tex kitten_tex;
static float angleX = 0.0, angleY = 0.0;
 
// Helper function for loading a texture from memory
static bool loadTextureFromMem(C3D_Tex* tex, C3D_TexCube* cube, const void* data, size_t size)
{
 Tex3DS_Texture t3x = Tex3DS_TextureImport(data, size, tex, cube, false);
 if (!t3x)
 return false;
 
 // Delete the t3x object since we don't need it
 Tex3DS_TextureFree(t3x);
 return true;
}
 
static void sceneInit(void)
{
 // Load the vertex shader, create a shader program and bind it
 vshader_dvlb = DVLB_ParseFile((u32*)vshader_shbin, vshader_shbin_size);
 shaderProgramInit(&program);
 shaderProgramSetVsh(&program, &vshader_dvlb->DVLE[0]);
 C3D_BindProgram(&program);
 
 // Get the location of the uniforms
 uLoc_projection = shaderInstanceGetUniformLocation(program.vertexShader, "projection");
 uLoc_modelView = shaderInstanceGetUniformLocation(program.vertexShader, "modelView");
 uLoc_lightVec = shaderInstanceGetUniformLocation(program.vertexShader, "lightVec");
 uLoc_lightHalfVec = shaderInstanceGetUniformLocation(program.vertexShader, "lightHalfVec");
 uLoc_lightClr = shaderInstanceGetUniformLocation(program.vertexShader, "lightClr");
 uLoc_material = shaderInstanceGetUniformLocation(program.vertexShader, "material");
 
 // Configure attributes for use with the vertex shader
 C3D_AttrInfo* attrInfo = C3D_GetAttrInfo();
 AttrInfo_Init(attrInfo);
 AttrInfo_AddLoader(attrInfo, 0, GPU_FLOAT, 3); // v0=position
 AttrInfo_AddLoader(attrInfo, 1, GPU_FLOAT, 2); // v1=texcoord
 AttrInfo_AddLoader(attrInfo, 2, GPU_FLOAT, 3); // v2=normal
 
 // Compute the projection matrix
 Mtx_PerspTilt(&projection, C3D_AngleFromDegrees(80.0f), C3D_AspectRatioTop, 0.01f, 1000.0f, false);
 
 // Create the VBO (vertex buffer object)
 vbo_data = linearAlloc(sizeof(vertex_list));
 memcpy(vbo_data, vertex_list, sizeof(vertex_list));
 
 // Configure buffers
 C3D_BufInfo* bufInfo = C3D_GetBufInfo();
 BufInfo_Init(bufInfo);
 BufInfo_Add(bufInfo, vbo_data, sizeof(vertex), 3, 0x210);
 
 // Load the texture and bind it to the first texture unit
 if (!loadTextureFromMem(&kitten_tex, NULL, kitten_t3x, kitten_t3x_size))
 svcBreak(USERBREAK_PANIC);
 C3D_TexSetFilter(&kitten_tex, GPU_LINEAR, GPU_NEAREST);
 C3D_TexBind(0, &kitten_tex);
 
 // Configure the first fragment shading substage to blend the texture color with
 // the vertex color (calculated by the vertex shader using a lighting algorithm)
 // See https://www.opengl.org/sdk/docs/man2/xhtml/glTexEnv.xml for more insight
 C3D_TexEnv* env = C3D_GetTexEnv(0);
 C3D_TexEnvInit(env);
 C3D_TexEnvSrc(env, C3D_Both, GPU_TEXTURE0, GPU_PRIMARY_COLOR, 0);
 C3D_TexEnvFunc(env, C3D_Both, GPU_MODULATE);
}
 
static void sceneRender(void)
{
 // Calculate the modelView matrix
 C3D_Mtx modelView;
 Mtx_Identity(&modelView);
 Mtx_Translate(&modelView, 0.0, 0.0, -2.0 + 0.5*sinf(angleX), true);
 Mtx_RotateX(&modelView, angleX, true);
 Mtx_RotateY(&modelView, angleY, true);
 
 // Rotate the cube each frame
 angleX += M_PI / 180;
 angleY += M_PI / 360;
 
 // Update the uniforms
 C3D_FVUnifMtx4x4(GPU_VERTEX_SHADER, uLoc_projection, &projection);
 C3D_FVUnifMtx4x4(GPU_VERTEX_SHADER, uLoc_modelView, &modelView);
 C3D_FVUnifMtx4x4(GPU_VERTEX_SHADER, uLoc_material, &material);
 C3D_FVUnifSet(GPU_VERTEX_SHADER, uLoc_lightVec, 0.0f, 0.0f, -1.0f, 0.0f);
 C3D_FVUnifSet(GPU_VERTEX_SHADER, uLoc_lightHalfVec, 0.0f, 0.0f, -1.0f, 0.0f);
 C3D_FVUnifSet(GPU_VERTEX_SHADER, uLoc_lightClr, 1.0f, 1.0f, 1.0f, 1.0f);
 
 // Draw the VBO
 C3D_DrawArrays(GPU_TRIANGLES, 0, vertex_list_count);
}
 
static void sceneExit(void)
{
 // Free the texture
 C3D_TexDelete(&kitten_tex);
 
 // Free the VBO
 linearFree(vbo_data);
 
 // Free the shader program
 shaderProgramFree(&program);
 DVLB_Free(vshader_dvlb);
}
 
int main()
{
 // Initialize graphics
 gfxInitDefault();
 C3D_Init(C3D_DEFAULT_CMDBUF_SIZE);
 
 // Initialize the render target
 C3D_RenderTarget* target = C3D_RenderTargetCreate(240, 400, GPU_RB_RGBA8, GPU_RB_DEPTH24_STENCIL8);
 C3D_RenderTargetSetOutput(target, GFX_TOP, GFX_LEFT, DISPLAY_TRANSFER_FLAGS);
 
 // Initialize the scene
 sceneInit();
 
 // Main loop
 while (aptMainLoop())
 {
 hidScanInput();
 
 // Respond to user input
 u32 kDown = hidKeysDown();
 if (kDown & KEY_START)
 break; // break in order to return to hbmenu
 
 // Render the scene
 C3D_FrameBegin(C3D_FRAME_SYNCDRAW);
 C3D_RenderTargetClear(target, C3D_CLEAR_ALL, CLEAR_COLOR, 0);
 C3D_FrameDrawOn(target);
 sceneRender();
 C3D_FrameEnd(0);
 }
 
 // Deinitialize the scene
 sceneExit();
 
 // Deinitialize graphics
 C3D_Fini();
 gfxExit();
 return 0;
}