diff options
| -rw-r--r-- | .gitignore | 2 | ||||
| -rwxr-xr-x | main.cpp | 162 | ||||
| -rw-r--r-- | makefile | 11 |
3 files changed, 175 insertions, 0 deletions
diff --git a/.gitignore b/.gitignore new file mode 100644 index 0000000..ae07e71 --- /dev/null +++ b/.gitignore @@ -0,0 +1,2 @@ +*.ppm +render diff --git a/main.cpp b/main.cpp new file mode 100755 index 0000000..9b1ce8c --- /dev/null +++ b/main.cpp @@ -0,0 +1,162 @@ +#include<fstream> +#include<cmath> + +class Vertice +{ +public: + float x, y, z; + unsigned char red, green, blue; + Vertice(float x, float y, float z, int red, int green, int blue) + { + this->x = x; + this->y = y; + this->z = z; + + this->red = (unsigned char)red; + this->green = (unsigned char)green; + this->blue = (unsigned char)blue; + } + void fitToImage(int imageWidth, int imageHeight) + { + x = (x * (imageWidth / 2)) + (imageWidth / 2); + y = (-y * (imageHeight / 2)) + (imageHeight / 2); + } +}; + +class Image +{ +public: + int imageWidth, imageHeight; + unsigned char* pixels; + Image(int imageWidth, int imageHeight) + { + this->imageWidth = imageWidth; + this->imageHeight = imageHeight; + pixels = new unsigned char[imageWidth * imageHeight * 3]; + } + ~Image() + { + delete[] pixels; + } + void setPixel(int x, int y, int red, int green, int blue) + { + int help_var = ((y * imageWidth) + x) * 3; + pixels[help_var + 0] = (unsigned char)red; + pixels[help_var + 1] = (unsigned char)green; + pixels[help_var + 2] = (unsigned char)blue; + } + void fillPixels(int red, int green, int blue) + { + int help_var = imageWidth * imageHeight * 3; + for (int i = 0; i < help_var; i += 3) { + pixels[i + 0] = (unsigned char)red; + pixels[i + 1] = (unsigned char)green; + pixels[i + 2] = (unsigned char)blue; + } + } + //-------------------SCANLINE TRIANGLE RASTERISATION--------------------------- + void fillFlatTopTriangle(Vertice* v1, Vertice* v2, Vertice* v3) + { + float invslope1 = (float)(v3->x - v1->x) / (float)(v3->y - v1->y); + float invslope2 = (float)(v3->x - v2->x) / (float)(v3->y - v2->y); + + float curx1 = v3->x; + float curx2 = v3->x; + int cury1 = (int)ceil(v1->y - 0.5f); + int cury2 = (int)ceil(v3->y - 0.5f); + + for (int i = cury2; i >= cury1; i--) + { + if(curx1 < curx2) + for (int j = (int)ceil(curx1 - 0.5f); j <= (int)ceil(curx2 - 0.5f); j++) + setPixel(j, i, 255, 0, 0); + else + for (int j = (int)ceil(curx2 - 0.5f); j <= (int)ceil(curx1 - 0.5f); j++) + setPixel(j, i, 255, 0, 0); + + curx1 -= invslope1; + curx2 -= invslope2; + } + } + void fillFlatBottomTriangle(Vertice* v1, Vertice* v2, Vertice* v3) + { + float invslope1 = (float)(v2->x - v1->x) / (float)(v2->y - v1->y); + float invslope2 = (float)(v3->x - v1->x) / (float)(v3->y - v1->y); + + float curx1 = v1->x; + float curx2 = v1->x; + int cury1 = (int)ceil(v1->y - 0.5f); + int cury2 = (int)ceil(v2->y - 0.5f); + for (int i = cury1; i <= cury2; i++) + { + if(curx1 < curx2) + for (int j = (int)ceil(curx1 - 0.5f); j <= (int)ceil(curx2 - 0.5f); j++) + setPixel(j, i, 255, 0, 0); + else + for (int j = (int)ceil(curx2 - 0.5f); j <= (int)ceil(curx1 - 0.5f); j++) + setPixel(j, i, 255, 0, 0); + + curx1 += invslope1; + curx2 += invslope2; + } + } + void fillTriangle(Vertice* v1, Vertice* v2, Vertice* v3) + { + if (v1->y > v2->y) + std::swap(v1, v2); + if (v1->y > v3->y) + std::swap(v1, v3); + if (v2->y > v3->y) + std::swap(v2, v3); + + if (v2->y == v3->y){ + if(v2->x < v3->x) + std::swap(v2, v3); + fillFlatBottomTriangle(v1, v2, v3); + } + else if (v1->y == v2->y){ + if(v1->x < v2->x) + std::swap(v1, v2); + fillFlatTopTriangle(v1, v2, v3); + } + else + { + Vertice v4( + (v1->x + (((float)(v2->y - v1->y) / (float)(v3->y - v1->y)) * (v3->x - v1->x))), v2->y, 0.0f, 0, 0, 0); + if(v1->x < v4.x){ + fillFlatBottomTriangle(v1, v2, &v4); + fillFlatTopTriangle(v2, &v4, v3); + } + else{ + fillFlatBottomTriangle(v1, &v4, v2); + fillFlatTopTriangle(&v4, v2, v3); + } + } + + } + //----------------------------------------------------------------------------- +}; + +int main() +{ + Image image(800, 600); + image.fillPixels(255, 255, 255); + + Vertice a(0.2f, 0.5f, 0.0f, 255, 0, 0); + Vertice b(-0.5f, 0.0f, 0.0f, 0, 255, 0); + Vertice c(0.5f, -0.5f, 0.0f, 0, 0, 255); + + a.fitToImage(image.imageWidth, image.imageHeight); + b.fitToImage(image.imageWidth, image.imageHeight); + c.fitToImage(image.imageWidth, image.imageHeight); + + image.fillTriangle(&a, &b, &c); + + std::ofstream imageFile; + imageFile.open("./image.ppm"); + imageFile << "P6\n" << image.imageWidth << " " << image.imageHeight << "\n255\n"; + imageFile.write((char*)image.pixels, image.imageWidth * image.imageHeight * 3); + imageFile.close(); + + return 0; +} diff --git a/makefile b/makefile new file mode 100644 index 0000000..0a4fca9 --- /dev/null +++ b/makefile @@ -0,0 +1,11 @@ +render: main.cpp + g++ -o render main.cpp +image.ppm: render + ./render +run: render + ./render +view: image.ppm + feh -. image.ppm +clean: + rm image.ppm + rm render |